PATENT DOCUMENT

Publication Number: US-10884608-B2
Application Number: US-201916354035-A
Country: US
Kind Code: B2

Title: Devices, methods, and graphical user interfaces for content navigation and manipulation

Abstract:
An electronic device displays content of a first content item, wherein the first content item is one of a sequence of content items. The device detects a user input that includes movement of a contact in a respective direction on the touch-sensitive surface. In response to detecting the user input: in accordance with a determination that the user input meets item-switching criteria, the device replaces display of the first content item with display of a second content item in the sequence of content items, wherein the item-switching criteria include a criterion that is met when a characteristic intensity of the contact is above a first intensity threshold; and, in accordance with a determination that the user input does not meet the item-switching criteria, the device navigates through the content of the first content item in accordance with the movement of the contact.

Claims:
What is claimed is: 
     
       1. A non-transitory computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensities of contacts with the touch-sensitive surface, cause the electronic device to:
 display, on the display, content of a first content item, wherein the first content item is one of a sequence of content items; 
 detect a user input that includes movement of a contact in a respective direction on the touch-sensitive surface; and 
 in response to detecting the user input:
 in accordance with a determination that the user input meets item-switching criteria, replace display of the first content item with display of a second content item in the sequence of content items, wherein the item-switching criteria include a criterion that is met when a characteristic intensity of the contact is above a first intensity threshold; and, 
 in accordance with a determination that the user input does not meet the item-switching criteria, navigate through the content of the first content item in accordance with the movement of the contact. 
 
 
     
     
       2. The non-transitory computer readable storage medium of  claim 1 , wherein the item-switching criteria include a criterion that is met when the characteristic intensity of the contact exceeds the first intensity threshold after detecting at least a predetermined threshold amount of movement of the contact. 
     
     
       3. The non-transitory computer readable storage medium of  claim 1 , wherein the user input is a first user input, and the one or more programs include instructions, which when executed by the electronic device, cause the electronic device to:
 while displaying the first content item, detect a second user input at a location that corresponds to a selectable affordance, wherein the second user input includes a second contact on the touch-sensitive surface; and 
 in response to detecting the second user input:
 in accordance with a determination that
 the second user input occurs while a focus selector is at a location that corresponds to the selectable affordance, and 
 the movement of the second contact is less than a predetermined amount, 
 display a preview area of content that corresponds to the selectable affordance overlaid on the first content item. 
 
 
 
     
     
       4. The non-transitory computer readable storage medium of  claim 1 , wherein the second content item is sequentially adjacent to the first content item in the sequence of content items and is selected based on the respective direction of the movement of the contact. 
     
     
       5. The non-transitory computer readable storage medium of  claim 1 , wherein navigating through the content of the first content item includes:
 in accordance with a determination that the respective direction is a first direction on the touch-sensitive surface, scrolling the content in a first direction on the display; and 
 in accordance with a determination that the respective direction is a second direction on the touch-sensitive surface, scrolling the content in a second direction on the display that is different from the first direction on the display. 
 
     
     
       6. The non-transitory computer readable storage medium of  claim 1 , wherein navigating through the content of the first content item in accordance with the movement of the contact includes:
 maintaining display of a first portion of the first content item in a first user interface region on the display; and 
 navigating through a second portion of the first content item in a second user interface region on the display. 
 
     
     
       7. The non-transitory computer readable storage medium of  claim 1 , wherein:
 replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item; and 
 the transition includes reducing a size of the first content item. 
 
     
     
       8. The non-transitory computer readable storage medium of  claim 1 , wherein:
 replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item; and 
 the transition includes increasing a size of the second content item. 
 
     
     
       9. The non-transitory computer readable storage medium of  claim 1 , wherein the sequence of content items corresponds to a plurality of electronic messages in an electronic messaging application, a plurality of web browser windows in a web browser, a plurality of applications, a plurality of digital images in a set of images, or a plurality of sets of digital images. 
     
     
       10. The non-transitory computer readable storage medium of  claim 1 , wherein the one or more programs include instructions, which when executed by the electronic device, cause the electronic device to:
 in accordance with a determination that the user input begins at a first edge of the touch-sensitive surface, perform an operation that is distinct from both replacing display of the first content item with the second content item and navigating through the content of the first content item. 
 
     
     
       11. The non-transitory computer readable storage medium of  claim 1 , wherein the user input is a first user input, and the one or more programs include instructions, which when executed by the electronic device, cause the electronic device to:
 after replacing display of the first content item with the second content item in the sequence of content items, detect a second user input that includes movement of a second contact on the touch-sensitive surface; and 
 in response to detecting the second user input:
 in accordance with a determination that the second user input meets the item-switching criteria, replace display of the second content item with a third content item in the sequence of content items; and 
 in accordance with a determination that the second user input does not meet the item-switching criteria, navigate through content of the second content item in accordance with the movement of the second contact. 
 
 
     
     
       12. An electronic device, comprising: 
       a display; 
       a touch-sensitive surface; 
       one or more sensors to detect intensities of contacts with the touch-sensitive surface; 
       one or more processors; 
       memory; and 
       one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for:
 displaying, on the display, content of a first content item, wherein the first content item is one of a sequence of content items; 
 detecting a user input that includes movement of a contact in a respective direction on the touch-sensitive surface; and 
 in response to detecting the user input:
 in accordance with a determination that the user input meets item-switching criteria, replacing display of the first content item with display of a second content item in the sequence of content items, wherein the item-switching criteria include a criterion that is met when a characteristic intensity of the contact is above a first intensity threshold; and, 
 in accordance with a determination that the user input does not meet the item-switching criteria, navigating through the content of the first content item in accordance with the movement of the contact. 
 
 
     
     
       13. The electronic device of  claim 12 , wherein the item-switching criteria include a criterion that is met when the characteristic intensity of the contact exceeds the first intensity threshold after detecting at least a predetermined threshold amount of movement of the contact. 
     
     
       14. The electronic device of  claim 12 , wherein the user input is a first user input, and the one or more programs include instructions for:
 while displaying the first content item, detecting a second user input at a location that corresponds to a selectable affordance, wherein the second user input includes a second contact on the touch-sensitive surface; and 
 in response to detecting the second user input:
 in accordance with a determination that
 the second user input occurs while a focus selector is at a location that corresponds to the selectable affordance, and 
 the movement of the second contact is less than a predetermined amount, 
 displaying a preview area of content that corresponds to the selectable affordance overlaid on the first content item. 
 
 
 
     
     
       15. The electronic device of  claim 12 , wherein the second content item is sequentially adjacent to the first content item in the sequence of content items and is selected based on the respective direction of the movement of the contact. 
     
     
       16. The electronic device of  claim 12 , wherein navigating through the content of the first content item includes:
 in accordance with a determination that the respective direction is a first direction on the touch-sensitive surface, scrolling the content in a first direction on the display; and 
 in accordance with a determination that the respective direction is a second direction on the touch-sensitive surface, scrolling the content in a second direction on the display that is different from the first direction on the display. 
 
     
     
       17. The electronic device of  claim 12 , wherein navigating through the content of the first content item in accordance with the movement of the contact includes:
 maintaining display of a first portion of the first content item in a first user interface region on the display; and 
 navigating through a second portion of the first content item in a second user interface region on the display. 
 
     
     
       18. The electronic device of  claim 12 , wherein:
 replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item; and 
 the transition includes reducing a size of the first content item. 
 
     
     
       19. The electronic device of  claim 12 , wherein:
 replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item; and 
 the transition includes increasing a size of the second content item. 
 
     
     
       20. The electronic device of  claim 12 , wherein the sequence of content items corresponds to a plurality of electronic messages in an electronic messaging application, a plurality of web browser windows in a web browser, a plurality of applications, a plurality of digital images in a set of images, or a plurality of sets of digital images. 
     
     
       21. The electronic device of  claim 12 , wherein the one or more programs include instructions for:
 in accordance with a determination that the user input begins at a first edge of the touch-sensitive surface, performing an operation that is distinct from both replacing display of the first content item with the second content item and navigating through the content of the first content item. 
 
     
     
       22. The electronic device of  claim 12 , wherein the user input is a first user input, and the one or more programs include instructions for:
 after replacing display of the first content item with the second content item in the sequence of content items, detecting a second user input that includes movement of a second contact on the touch-sensitive surface; and 
 in response to detecting the second user input:
 in accordance with a determination that the second user input meets the item-switching criteria, replacing display of the second content item with a third content item in the sequence of content items; and 
 in accordance with a determination that the second user input does not meet the item-switching criteria, navigating through content of the second content item in accordance with the movement of the second contact. 
 
 
     
     
       23. A method, comprising: 
       at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensities of contacts with the touch-sensitive surface:
 displaying, on the display, content of a first content item, wherein the first content item is one of a sequence of content items; 
 detecting a user input that includes movement of a contact in a respective direction on the touch-sensitive surface; and 
 in response to detecting the user input:
 in accordance with a determination that the user input meets item-switching criteria, replacing display of the first content item with display of a second content item in the sequence of content items, wherein the item-switching criteria include a criterion that is met when a characteristic intensity of the contact is above a first intensity threshold; and, 
 in accordance with a determination that the user input does not meet the item-switching criteria, navigating through the content of the first content item in accordance with the movement of the contact. 
 
 
     
     
       24. The method of  claim 23 , wherein the item-switching criteria include a criterion that is met when the characteristic intensity of the contact exceeds the first intensity threshold after detecting at least a predetermined threshold amount of movement of the contact. 
     
     
       25. The method of  claim 23 , wherein the user input is a first user input, and the method includes:
 while displaying the first content item, detecting a second user input at a location that corresponds to a selectable affordance, wherein the second user input includes a second contact on the touch-sensitive surface; and 
 in response to detecting the second user input:
 in accordance with a determination that
 the second user input occurs while a focus selector is at a location that corresponds to the selectable affordance, and 
 the movement of the second contact is less than a predetermined amount, 
 displaying a preview area of content that corresponds to the selectable affordance overlaid on the first content item. 
 
 
 
     
     
       26. The method of  claim 23 , wherein the second content item is sequentially adjacent to the first content item in the sequence of content items and is selected based on the respective direction of the movement of the contact. 
     
     
       27. The method of  claim 23 , including:
 in accordance with a determination that the respective direction is a first direction on the touch-sensitive surface, scrolling the content in a first direction on the display; and 
 in accordance with a determination that the respective direction is a second direction on the touch-sensitive surface, scrolling the content in a second direction on the display that is different from the first direction on the display. 
 
     
     
       28. The method of  claim 23 , wherein navigating through the content of the first content item in accordance with the movement of the contact includes:
 maintaining display of a first portion of the first content item in a first user interface region on the display; and 
 navigating through a second portion of the first content item in a second user interface region on the display. 
 
     
     
       29. The method of  claim 23 , wherein:
 replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item; and 
 the transition includes reducing a size of the first content item. 
 
     
     
       30. The method of  claim 23 , wherein:
 replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item; and 
 the transition includes increasing a size of the second content item. 
 
     
     
       31. The method of  claim 23 , wherein the sequence of content items corresponds to a plurality of electronic messages in an electronic messaging application, a plurality of web browser windows in a web browser, a plurality of applications, a plurality of digital images in a set of images, or a plurality of sets of digital images. 
     
     
       32. The method of  claim 23 , including:
 in accordance with a determination that the user input begins at a first edge of the touch-sensitive surface, performing an operation that is distinct from both replacing display of the first content item with the second content item and navigating through the content of the first content item. 
 
     
     
       33. The method of  claim 23 , wherein the user input is a first user input, and the method includes:
 after replacing display of the first content item with the second content item in the sequence of content items, detecting a second user input that includes movement of a second contact on the touch-sensitive surface; and 
 in response to detecting the second user input:
 in accordance with a determination that the second user input meets the item-switching criteria, replacing display of the second content item with a third content item in the sequence of content items; and 
 in accordance with a determination that the second user input does not meet the item-switching criteria, navigating through content of the second content item in accordance with the movement of the second contact.

Description:
RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 15/009,688, filed Jan. 28, 2016, which claims priority to U.S. Provisional Application Ser. No. 62/235,490, filed Sep. 30, 2015, and U.S. Provisional Application Ser. No. 62/203,387, filed Aug. 10, 2015, all of which are incorporated by reference herein in their entireties. 
    
    
     TECHNICAL FIELD 
     This relates generally to electronic devices with touch-sensitive surfaces, including but not limited to electronic devices with touch-sensitive surfaces used for navigating and manipulating displayed content. 
     BACKGROUND 
     The use of touch-sensitive surfaces as input devices for computers and other electronic computing devices has increased significantly in recent years. Exemplary touch-sensitive surfaces include touchpads and touch-screen displays. Such surfaces are widely used to navigate and manipulate content in user interfaces on a display. 
     Exemplary types of navigation and manipulation include scrolling, zooming, and adjusting the position and/or size of one or more user interface objects, as well as reordering user interface objects. Exemplary user interface objects include digital images, video, text, icons, control elements such as buttons, and other graphics. A user will, in some circumstances, need to navigate and manipulate content in a reader application (e.g., iBooks from Apple Inc. of Cupertino, Calif.), a file management program (e.g., Finder from Apple Inc. of Cupertino, Calif.), an image management application (e.g., Aperture, iPhoto, Photos from Apple Inc. of Cupertino, Calif.), a digital content (e.g., videos and music) management application (e.g., iTunes from Apple Inc. of Cupertino, Calif.), a drawing application, a presentation application (e.g., Keynote from Apple Inc. of Cupertino, Calif.), a word processing application (e.g., Pages from Apple Inc. of Cupertino, Calif.), or a spreadsheet application (e.g., Numbers from Apple Inc. of Cupertino, Calif.). 
     But existing methods for performing these navigations and manipulations are cumbersome and inefficient. In addition, these methods take longer than necessary, thereby wasting energy. This latter consideration is particularly important in battery-operated devices. 
     SUMMARY 
     Accordingly, there is a need for electronic devices with faster, more efficient methods and interfaces for content navigation and manipulation. Such methods and interfaces optionally complement or replace conventional methods for content navigation and manipulation. Such methods and interfaces reduce the number, extent, and/or nature of the inputs from a user and produce a more efficient human-machine interface. For battery-operated devices, such methods and interfaces conserve power and increase the time between battery charges. 
     The above deficiencies and other problems associated with user interfaces for electronic devices with touch-sensitive surfaces are reduced or eliminated by the disclosed devices. In some embodiments, the device is a desktop computer. In some embodiments, the device is portable (e.g., a notebook computer, tablet computer, or handheld device). In some embodiments, the device is a personal electronic device (e.g., a wearable electronic device, such as a watch). In some embodiments, the device has a touchpad. In some embodiments, the device has a touch-sensitive display (also known as a “touch screen” or “touch-screen display”). In some embodiments, the device has a graphical user interface (GUI), one or more processors, memory and one or more modules, programs or sets of instructions stored in the memory for performing multiple functions. In some embodiments, the user interacts with the GUI primarily through stylus and/or finger contacts and gestures on the touch-sensitive surface. In some embodiments, the functions optionally include document reading, image editing, drawing, presenting, word processing, spreadsheet making, game playing, telephoning, video conferencing, e-mailing, instant messaging, workout support, digital photographing, digital videoing, web browsing, digital music playing, note taking, and/or digital video playing. Executable instructions for performing these functions are, optionally, included in a non-transitory computer readable storage medium or other computer program product configured for execution by one or more processors. 
     In accordance with some embodiments, a method is performed at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. The method includes: displaying, on the display, content of a first content item, wherein the first content item is one of a sequence of content items. The device detects a user input that includes movement of a contact in a respective direction on the touch-sensitive surface. In response to detecting the user input: in accordance with a determination that the user input meets item-switching criteria, the device replaces display of the first content item with display of a second content item in the sequence of content items, wherein the item-switching criteria include a criterion that is met when a characteristic intensity of the contact is above a first intensity threshold; and, in accordance with a determination that the user input does not meet the item-switching criteria, the device navigates through the content of the first content item in accordance with the movement of the contact. 
     In accordance with some embodiments, a method is performed at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. The method includes: presenting a first portion of a list of items on the display. The device detects a contact on the touch-sensitive surface while the first portion of the list of items is presented on the display and a first movement of the contact on the touch-sensitive surface while a characteristic intensity of the contact remains below a first intensity threshold. In response to detecting the first movement of the contact on the touch-sensitive surface while the characteristic intensity of the contact remains below the first intensity threshold, the device scrolls the list of items to present a second portion of the list of items on the display in accordance with the first movement of the contact on the touch-sensitive surface. While a focus selector associated with the contact is located on a first item in the second portion of the list of items presented on the display, the device detects an increase in the characteristic intensity of the contact above the first intensity threshold followed by a second movement of the contact on the touch-sensitive surface. In response to detecting the increase in the characteristic intensity of the contact above the first intensity threshold followed by the second movement of the contact on the touch-sensitive surface, the device moves the first item relative to other items in the second portion of the list of items presented on the display in accordance with the second movement of the contact. 
     In accordance with some embodiments, a method is performed at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. The method includes: presenting a first portion of structured content on the display. The structured content includes a plurality of sections, and the first portion includes content from a first section of the plurality of sections. The device detects a first contact on the touch-sensitive surface while the first portion of the structured content is presented on the display. The device detects an increase in a characteristic intensity of the first contact on the touch-sensitive surface and detects a first movement of the first contact on the touch-sensitive surface. In response to detecting the increase in the characteristic intensity of the first contact and detecting the first movement of the first contact: in accordance with a determination that the characteristic intensity of the contact increases above a first intensity threshold, the device translates the structured content to display a start of a second section adjacent to the first section of the structured content at a predefined location on the display; and in accordance with a determination that the characteristic intensity of the contact does not increase above the first intensity threshold, the device translates the structured content in accordance with a magnitude of the movement of the contact on the touch-sensitive surface. 
     In accordance with some embodiments, a method is performed at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. The method includes: presenting a first portion of content on the display. While presenting the first portion of the content on the display, the device detects a first contact on the touch-sensitive surface and detects a first movement of the first contact on the touch-sensitive surface. In response to detecting the first movement of the first contact, the device scrolls the content to present a second portion of the content on the display in accordance with the first movement of the first contact. The device detects an increase in intensity of the first contact on the touch-sensitive surface during the first movement of the first contact on the touch-sensitive surface. After detecting the increase in intensity of the first contact on the touch-sensitive surface during the first movement of the first contact on the touch-sensitive surface, the device detects a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface. In response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface, the device moves the content on the display by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact. 
     In accordance with some embodiments, a method is performed at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. The method includes: presenting a first portion of content on the display. While presenting the first portion of the content, the device detects a first contact on the touch-sensitive surface and detects a first movement of the first contact on the touch-sensitive surface. The device detects a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface. In response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface: in accordance with a determination that the first contact had a characteristic intensity above a respective intensity threshold prior to the lift-off of the first contact, the device scrolls through the content to a predefined portion of the content; and in accordance with a determination that the first contact had a characteristic intensity below the respective intensity threshold prior to the lift-off of the first contact, the device scrolls through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement. 
     In accordance with some embodiments, an electronic device includes a display unit configured to display a user interface, a touch-sensitive surface unit to receive contacts, one or more sensor units to detect intensity of contacts with the touch-sensitive surface unit; and a processing unit coupled with the display unit, the touch-sensitive surface unit, and the one or more sensor units. The processing unit is configured to: enable display, on the display unit, of content of a first content item, wherein the first content item is one of a sequence of content items; detect a user input that includes movement of a contact in a respective direction on the touch-sensitive surface unit; in response to detecting the user input: in accordance with a determination that the user input meets item-switching criteria, enable the display unit to replace display of the first content item with display of a second content item in the sequence of content items, wherein the item-switching criteria include a criterion that is met when a characteristic intensity of the contact is above a first intensity threshold; and, in accordance with a determination that the user input does not meet the item-switching criteria, enable the display unit to navigate through the content of the first content item in accordance with the movement of the contact. 
     In accordance with some embodiments, an electronic device includes a display unit configured to display a user interface, a touch-sensitive surface unit to receive contacts, one or more sensor units to detect intensity of contacts with the touch-sensitive surface unit; and a processing unit coupled with the display unit, the touch-sensitive surface unit, and the one or more sensor units. The processing unit is configured to: present a first portion of a list of items on the display unit; detect a contact on the touch-sensitive surface unit while the first portion of the list of items is presented on the display unit; detect a first movement of the contact on the touch-sensitive surface unit while a characteristic intensity of the contact remains below a first intensity threshold; in response to detecting the first movement of the contact on the touch-sensitive surface unit while the characteristic intensity of the contact remains below the first intensity threshold, scroll the list of items to present a second portion of the list of items on the display unit in accordance with the first movement of the contact on the touch-sensitive surface unit; while a focus selector associated with the contact is located on a first item in the second portion of the list of items presented on the display unit, detect an increase in the characteristic intensity of the contact above the first intensity threshold followed by a second movement of the contact on the touch-sensitive surface unit; and, in response to detecting the increase in the characteristic intensity of the contact above the first intensity threshold followed by the second movement of the contact on the touch-sensitive surface unit, move the first item relative to other items in the second portion of the list of items presented on the display unit in accordance with the second movement of the contact. 
     In accordance with some embodiments, an electronic device includes a display unit configured to display a user interface, a touch-sensitive surface unit to receive contacts, one or more sensor units to detect intensity of contacts with the touch-sensitive surface unit; and a processing unit coupled with the display unit, the touch-sensitive surface unit, and the one or more sensor units. The processing unit is configured to: present a first portion of structured content on the display unit, wherein the structured content includes a plurality of sections, and the first portion includes content from a first section of the plurality of sections; detect a first contact on the touch-sensitive surface unit while the first portion of the structured content is presented on the display unit; detect an increase in a characteristic intensity of the first contact on the touch-sensitive surface unit and detecting a first movement of the first contact on the touch-sensitive surface unit; and, in response to detecting the increase in the characteristic intensity of the first contact and detecting the first movement of the first contact: in accordance with a determination that the characteristic intensity of the contact increases above a first intensity threshold, translate the structured content to enable display of a start of a second section adjacent to the first section of the structured content at a predefined location on the display unit; and, in accordance with a determination that the characteristic intensity of the contact does not increase above the first intensity threshold, translate the structured content in accordance with a magnitude of the movement of the contact on the touch-sensitive surface unit. 
     In accordance with some embodiments, an electronic device includes a display unit configured to display a user interface, a touch-sensitive surface unit to receive contacts, one or more sensor units to detect intensity of contacts with the touch-sensitive surface unit; and a processing unit coupled with the display unit, the touch-sensitive surface unit, and the one or more sensor units. The processing unit is configured to: present a first portion of content on the display unit; while presenting the first portion of the content on the display unit: detect a first contact on the touch-sensitive surface unit; and detect a first movement of the first contact on the touch-sensitive surface unit; in response to detecting the first movement of the first contact, scroll the content to present a second portion of the content on the display unit in accordance with the first movement of the first contact; detect an increase in intensity of the first contact on the touch-sensitive surface unit during the first movement of the first contact on the touch-sensitive surface unit; after detecting the increase in intensity of the first contact on the touch-sensitive surface unit during the first movement of the first contact on the touch-sensitive surface unit, detect a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit; and, in response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit, move the content on the display unit by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact. 
     In accordance with some embodiments, an electronic device includes a display unit configured to display a user interface, a touch-sensitive surface unit to receive contacts, one or more sensor units to detect intensity of contacts with the touch-sensitive surface unit; and a processing unit coupled with the display unit, the touch-sensitive surface unit, and the one or more sensor units. The processing unit is configured to: present a first portion of content on the display unit; while presenting the first portion of the content: detect a first contact on the touch-sensitive surface unit; and detect a first movement of the first contact on the touch-sensitive surface unit; detect a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit; and, in response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit: in accordance with a determination that the first contact had a characteristic intensity above a respective intensity threshold prior to the lift-off of the first contact, scroll through the content to a predefined portion of the content; and in accordance with a determination that the first contact had a characteristic intensity below the respective intensity threshold prior to the lift-off of the first contact, scroll through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement. 
     In accordance with some embodiments, an electronic device includes a display, a touch-sensitive surface, optionally one or more sensors to detect intensity of contacts with the touch-sensitive surface, one or more processors, memory, and one or more programs; the one or more programs are stored in the memory and configured to be executed by the one or more processors and the one or more programs include instructions for performing or causing performance of the operations of any of the methods described herein. In accordance with some embodiments, a computer readable storage medium has stored therein instructions which when executed by an electronic device with a display, a touch-sensitive surface, and optionally one or more sensors to detect intensity of contacts with the touch-sensitive surface, cause the device to perform or cause performance of the operations of any of the methods described herein. In accordance with some embodiments, a graphical user interface on an electronic device with a display, a touch-sensitive surface, optionally one or more sensors to detect intensity of contacts with the touch-sensitive surface, a memory, and one or more processors to execute one or more programs stored in the memory includes one or more of the elements displayed in any of the methods described herein, which are updated in response to inputs, as described in any of the methods described herein. In accordance with some embodiments, an electronic device includes: a display, a touch-sensitive surface, and optionally one or more sensors to detect intensity of contacts with the touch-sensitive surface; and means for performing or causing performance of the operations of any of the methods described herein. In accordance with some embodiments, an information processing apparatus, for use in an electronic device with a display and a touch-sensitive surface, and optionally one or more sensors to detect intensity of contacts with the touch-sensitive surface, includes means for performing or causing performance of the operations of any of the methods described herein. 
     Thus, electronic devices with displays, touch-sensitive surfaces and optionally one or more sensors to detect intensity of contacts with the touch-sensitive surface are provided with faster, more efficient methods and interfaces for content navigation and manipulation, thereby increasing the effectiveness, efficiency, and user satisfaction with such devices. Such methods and interfaces may complement or replace conventional methods for content navigation and manipulation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the various described embodiments, reference should be made to the Description of Embodiments below, in conjunction with the following drawings in which like reference numerals refer to corresponding parts throughout the figures. 
         FIG. 1A  is a block diagram illustrating a portable multifunction device with a touch-sensitive display in accordance with some embodiments. 
         FIG. 1B  is a block diagram illustrating exemplary components for event handling in accordance with some embodiments. 
         FIG. 2  illustrates a portable multifunction device having a touch screen in accordance with some embodiments. 
         FIG. 3  is a block diagram of an exemplary multifunction device with a display and a touch-sensitive surface in accordance with some embodiments. 
         FIG. 4A  illustrates an exemplary user interface for a menu of applications on a portable multifunction device in accordance with some embodiments. 
         FIG. 4B  illustrates an exemplary user interface for a multifunction device with a touch-sensitive surface that is separate from the display in accordance with some embodiments. 
         FIGS. 4C-4E  illustrate exemplary dynamic intensity thresholds in accordance with some embodiments. 
         FIGS. 5A-5TT  illustrate exemplary user interfaces for navigating within and between content items in accordance with some embodiments. 
         FIGS. 6A-6B  are flow diagrams illustrating a method of navigating within and between content items in accordance with some embodiments. 
         FIGS. 7A-7C  are flow diagrams illustrating a method of reordering list items in accordance with some embodiments. 
         FIGS. 8A-8C  are flow diagrams illustrating a method of navigating structured content in accordance with some embodiments. 
         FIGS. 9A-9D  are flow diagrams illustrating a method of variable movement of content in accordance with some embodiments. 
         FIGS. 10A-10C  are flow diagrams illustrating a method of scrolling to a predefined portion of content in accordance with some embodiments. 
         FIGS. 11-15  are functional block diagrams of an electronic device in accordance with some embodiments. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Many electronic devices use graphical user interfaces to display user interface objects (e.g., content items). There is often a need to navigate the user interface objects, the position of one or more user interface objects with respect to the position of a different user interface object, or a component of the user interface object with respect to another component of the user interface object. Thus, there is a need to manipulate user interface objects in a fast, efficient, and convenient manner on an electronic device with a touch-sensitive surface. 
     Many electronic devices have graphical user interfaces that present lists of items such as digital content, bookmarks, locations (e.g., locations for which weather information is displayed) folders and/or other items. A user may need to move an item in a list to a different location in a list. For example, a user may reorder a playlist of digital content to change a location of a particular content item within the playlist. Here, methods are disclosed that streamline list reordering by enabling a user to use the same input gesture for list scrolling and list reordering functions. The function resulting from a gesture depends on a characteristic intensity of a contact in the gesture. Providing different functions resulting from the same input, based on an intensity component of the input, increases the range of controls available to a user. 
     Many electronic devices have graphical user interfaces with features for navigating structured content, such as graphical user interfaces for reader applications and other applications for displaying content. A user may need to access a start of a next section following a currently displayed section (or a prior section preceding the currently displayed section) of structured content. Some methods for accessing adjacent sections require a user to navigate using a menu or a slider control. With conventional scrolling using a slider control, the distance of the movement of the contact is closely correlated with the amount of content scrolling (e.g., lines, pages, etc.) that is performed. Here, methods are disclosed that streamline the structured content navigation process by allowing a user to translate structured content directly to an adjacent section using a defined input (regardless of the number of pages in the current section). Additionally, the user is enabled to translate either to an adjacent section or in accordance with a magnitude of movement of a contact, depending on a characteristic intensity of a contact in the input. 
     Many electronic devices have graphical user interfaces with features for scrolling through content, such as graphical user interfaces for reader applications and for other applications for displaying content. A user may need to scroll through content at different speeds at various times (e.g., in order to scroll through different amounts of content). With conventional scrolling, the distance of the movement of a contact is closely correlated with the movement of the contact before and after liftoff of the contact. Here, methods are disclosed that provide scrolling movement that changes in accordance with features of a contact in the input, including a characteristic intensity of the contact. 
     Many electronic devices have graphical user interfaces with features for scrolling through content, such as graphical user interfaces for reader applications and for other applications for displaying content. A user may need to scroll to a predefined portion of content. Some methods for accessing a portion of content require a user to continually scroll until the portion of the content is reached. Here, methods are disclosed that provide movement-based scrolling and scrolling to a predefined portion of content in accordance with a characteristic intensity of a contact in an input. 
     Below,  FIGS. 1A-1B, 2, and 3  provide a description of exemplary devices.  FIGS. 4A-4B and 5A-5TT  illustrate exemplary user interfaces for content navigation and manipulation.  FIGS. 6A-6B  illustrate a flow diagram of a method of navigating within and between content items.  FIGS. 7A-7C  illustrate a flow diagram of a method of reordering list items.  FIGS. 8A-8C  illustrate a flow diagram of a method of navigating structured content.  FIGS. 9A-9D  illustrate a flow diagram of a method of variable movement of content.  FIGS. 10A-10C  illustrate a flow diagram of a method of scrolling to a predefined portion of content. The user interfaces in  FIGS. 5A-5TT  are used to illustrate the processes in  FIGS. 6A-6B, 7A-7C, 8A-8C, 9A-9D, and 10A-10C . 
     Exemplary Devices 
     Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various described embodiments. However, it will be apparent to one of ordinary skill in the art that the various described embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments. 
     It will also be understood that, although the terms first, second, etc. are, in some instances, used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the scope of the various described embodiments. The first contact and the second contact are both contacts, but they are not the same contact, unless the context clearly indicates otherwise. 
     The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     As used herein, the term “if” is, optionally, construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” is, optionally, construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context. 
     Embodiments of electronic devices, user interfaces for such devices, and associated processes for using such devices are described. In some embodiments, the device is a portable communications device, such as a mobile telephone, that also contains other functions, such as PDA and/or music player functions. Exemplary embodiments of portable multifunction devices include, without limitation, the iPhone®, iPod Touch®, and iPad® devices from Apple Inc. of Cupertino, Calif. Other portable electronic devices, such as laptops or tablet computers with touch-sensitive surfaces (e.g., touch-screen displays and/or touchpads), are, optionally, used. It should also be understood that, in some embodiments, the device is not a portable communications device, but is a desktop computer with a touch-sensitive surface (e.g., a touch-screen display and/or a touchpad). 
     In the discussion that follows, an electronic device that includes a display and a touch-sensitive surface is described. It should be understood, however, that the electronic device optionally includes one or more other physical user-interface devices, such as a physical keyboard, a mouse and/or a joystick. 
     The device typically supports a variety of applications, such as one or more of the following: a note taking application, a drawing application, a presentation application, a word processing application, a website creation application, a disk authoring application, a spreadsheet application, a gaming application, a telephone application, a video conferencing application, an e-mail application, an instant messaging application, a workout support application, a photo management application, a digital camera application, a digital video camera application, a web browsing application, a digital music player application, and/or a digital video player application. 
     The various applications that are executed on the device optionally use at least one common physical user-interface device, such as the touch-sensitive surface. One or more functions of the touch-sensitive surface as well as corresponding information displayed on the device are, optionally, adjusted and/or varied from one application to the next and/or within a respective application. In this way, a common physical architecture (such as the touch-sensitive surface) of the device optionally supports the variety of applications with user interfaces that are intuitive and transparent to the user. 
     Attention is now directed toward embodiments of portable devices with touch-sensitive displays.  FIG. 1A  is a block diagram illustrating portable multifunction device  100  with touch-sensitive display system  112  in accordance with some embodiments. Touch-sensitive display system  112  is sometimes called a “touch screen” for convenience, and is sometimes simply called a touch-sensitive display. Device  100  includes memory  102  (which optionally includes one or more computer readable storage mediums), memory controller  122 , one or more processing units (CPUs)  120 , peripherals interface  118 , RF circuitry  108 , audio circuitry  110 , speaker  111 , microphone  113 , input/output (I/O) subsystem  106 , other input or control devices  116 , and external port  124 . Device  100  optionally includes one or more optical sensors  164 . Device  100  optionally includes one or more intensity sensors  165  for detecting intensity of contacts on device  100  (e.g., a touch-sensitive surface such as touch-sensitive display system  112  of device  100 ). Device  100  optionally includes one or more tactile output generators  167  for generating tactile outputs on device  100  (e.g., generating tactile outputs on a touch-sensitive surface such as touch-sensitive display system  112  of device  100  or touchpad  355  of device  300 ). These components optionally communicate over one or more communication buses or signal lines  103 . 
     As used in the specification and claims, the term “tactile output” refers to physical displacement of a device relative to a previous position of the device, physical displacement of a component (e.g., a touch-sensitive surface) of a device relative to another component (e.g., housing) of the device, or displacement of the component relative to a center of mass of the device that will be detected by a user with the user&#39;s sense of touch. For example, in situations where the device or the component of the device is in contact with a surface of a user that is sensitive to touch (e.g., a finger, palm, or other part of a user&#39;s hand), the tactile output generated by the physical displacement will be interpreted by the user as a tactile sensation corresponding to a perceived change in physical characteristics of the device or the component of the device. For example, movement of a touch-sensitive surface (e.g., a touch-sensitive display or trackpad) is, optionally, interpreted by the user as a “down click” or “up click” of a physical actuator button. In some cases, a user will feel a tactile sensation such as an “down click” or “up click” even when there is no movement of a physical actuator button associated with the touch-sensitive surface that is physically pressed (e.g., displaced) by the user&#39;s movements. As another example, movement of the touch-sensitive surface is, optionally, interpreted or sensed by the user as “roughness” of the touch-sensitive surface, even when there is no change in smoothness of the touch-sensitive surface. While such interpretations of touch by a user will be subject to the individualized sensory perceptions of the user, there are many sensory perceptions of touch that are common to a large majority of users. Thus, when a tactile output is described as corresponding to a particular sensory perception of a user (e.g., an “up click,” a “down click,” “roughness”), unless otherwise stated, the generated tactile output corresponds to physical displacement of the device or a component thereof that will generate the described sensory perception for a typical (or average) user. 
     It should be appreciated that device  100  is only one example of a portable multifunction device, and that device  100  optionally has more or fewer components than shown, optionally combines two or more components, or optionally has a different configuration or arrangement of the components. The various components shown in  FIG. 1A  are implemented in hardware, software, firmware, or a combination thereof, including one or more signal processing and/or application specific integrated circuits. 
     Memory  102  optionally includes high-speed random access memory and optionally also includes non-volatile memory, such as one or more magnetic disk storage devices, flash memory devices, or other non-volatile solid-state memory devices. Access to memory  102  by other components of device  100 , such as CPU(s)  120  and the peripherals interface  118 , is, optionally, controlled by memory controller  122 . 
     Peripherals interface  118  can be used to couple input and output peripherals of the device to CPU(s)  120  and memory  102 . The one or more processors  120  run or execute various software programs and/or sets of instructions stored in memory  102  to perform various functions for device  100  and to process data. 
     In some embodiments, peripherals interface  118 , CPU(s)  120 , and memory controller  122  are, optionally, implemented on a single chip, such as chip  104 . In some other embodiments, they are, optionally, implemented on separate chips. 
     RF (radio frequency) circuitry  108  receives and sends RF signals, also called electromagnetic signals. RF circuitry  108  converts electrical signals to/from electromagnetic signals and communicates with communications networks and other communications devices via the electromagnetic signals. RF circuitry  108  optionally includes well-known circuitry for performing these functions, including but not limited to an antenna system, an RF transceiver, one or more amplifiers, a tuner, one or more oscillators, a digital signal processor, a CODEC chipset, a subscriber identity module (SIM) card, memory, and so forth. RF circuitry  108  optionally communicates with networks, such as the Internet, also referred to as the World Wide Web (WWW), an intranet and/or a wireless network, such as a cellular telephone network, a wireless local area network (LAN) and/or a metropolitan area network (MAN), and other devices by wireless communication. The wireless communication optionally uses any of a plurality of communications standards, protocols and technologies, including but not limited to Global System for Mobile Communications (GSM), Enhanced Data GSM Environment (EDGE), high-speed downlink packet access (HSDPA), high-speed uplink packet access (HSUPA), Evolution, Data-Only (EV-DO), HSPA, HSPA+, Dual-Cell HSPA (DC-HSPDA), long term evolution (LTE), near field communication (NFC), wideband code division multiple access (W-CDMA), code division multiple access (CDMA), time division multiple access (TDMA), Bluetooth, Wireless Fidelity (Wi-Fi) (e.g., IEEE 802.11a, IEEE 802.11ac, IEEE 802.1 lax, IEEE 802.11b, IEEE 802.11g and/or IEEE 802.1 in), voice over Internet Protocol (VoIP), Wi-MAX, a protocol for e-mail (e.g., Internet message access protocol (IMAP) and/or post office protocol (POP)), instant messaging (e.g., extensible messaging and presence protocol (XMPP), Session Initiation Protocol for Instant Messaging and Presence Leveraging Extensions (SIMPLE), Instant Messaging and Presence Service (IMPS)), and/or Short Message Service (SMS), or any other suitable communication protocol, including communication protocols not yet developed as of the filing date of this document. 
     Audio circuitry  110 , speaker  111 , and microphone  113  provide an audio interface between a user and device  100 . Audio circuitry  110  receives audio data from peripherals interface  118 , converts the audio data to an electrical signal, and transmits the electrical signal to speaker  111 . Speaker  111  converts the electrical signal to human-audible sound waves. Audio circuitry  110  also receives electrical signals converted by microphone  113  from sound waves. Audio circuitry  110  converts the electrical signal to audio data and transmits the audio data to peripherals interface  118  for processing. Audio data is, optionally, retrieved from and/or transmitted to memory  102  and/or RF circuitry  108  by peripherals interface  118 . In some embodiments, audio circuitry  110  also includes a headset jack (e.g.,  212 ,  FIG. 2 ). The headset jack provides an interface between audio circuitry  110  and removable audio input/output peripherals, such as output-only headphones or a headset with both output (e.g., a headphone for one or both ears) and input (e.g., a microphone). 
     I/O subsystem  106  couples input/output peripherals on device  100 , such as touch-sensitive display system  112  and other input or control devices  116 , with peripherals interface  118 . I/O subsystem  106  optionally includes display controller  156 , optical sensor controller  158 , intensity sensor controller  159 , haptic feedback controller  161 , and one or more input controllers  160  for other input or control devices. The one or more input controllers  160  receive/send electrical signals from/to other input or control devices  116 . The other input or control devices  116  optionally include physical buttons (e.g., push buttons, rocker buttons, etc.), dials, slider switches, joysticks, click wheels, and so forth. In some alternate embodiments, input controller(s)  160  are, optionally, coupled with any (or none) of the following: a keyboard, infrared port, USB port, stylus, and/or a pointer device such as a mouse. The one or more buttons (e.g.,  208 ,  FIG. 2 ) optionally include an up/down button for volume control of speaker  111  and/or microphone  113 . The one or more buttons optionally include a push button (e.g.,  206 ,  FIG. 2 ). 
     Touch-sensitive display system  112  provides an input interface and an output interface between the device and a user. Display controller  156  receives and/or sends electrical signals from/to touch-sensitive display system  112 . Touch-sensitive display system  112  displays visual output to the user. The visual output optionally includes graphics, text, icons, video, and any combination thereof (collectively termed “graphics”). In some embodiments, some or all of the visual output corresponds to user interface objects. As used herein, the term “affordance” refers to a userlinteractive graphical user interface object (e.g., graphical user interface object that is configured to respond to inputs directed toward the graphical user interface object). Examples of userQinteractive graphical user interface objects include, without limitation, a button, slider, icon, selectable menu item, switch, or other user interface control. 
     Touch-sensitive display system  112  has a touch-sensitive surface, sensor or set of sensors that accepts input from the user based on haptic and/or tactile contact. Touch-sensitive display system  112  and display controller  156  (along with any associated modules and/or sets of instructions in memory  102 ) detect contact (and any movement or breaking of the contact) on touch-sensitive display system  112  and converts the detected contact into interaction with user-interface objects (e.g., one or more soft keys, icons, web pages or images) that are displayed on touch-sensitive display system  112 . In an exemplary embodiment, a point of contact between touch-sensitive display system  112  and the user corresponds to a finger of the user or a stylus. 
     Touch-sensitive display system  112  optionally uses LCD (liquid crystal display) technology, LPD (light emitting polymer display) technology, or LED (light emitting diode) technology, although other display technologies are used in other embodiments. Touch-sensitive display system  112  and display controller  156  optionally detect contact and any movement or breaking thereof using any of a plurality of touch sensing technologies now known or later developed, including but not limited to capacitive, resistive, infrared, and surface acoustic wave technologies, as well as other proximity sensor arrays or other elements for determining one or more points of contact with touch-sensitive display system  112 . In an exemplary embodiment, projected mutual capacitance sensing technology is used, such as that found in the iPhone®, iPod Touch®, and iPad® from Apple Inc. of Cupertino, Calif. 
     Touch-sensitive display system  112  optionally has a video resolution in excess of 100 dpi. In some embodiments, the touch screen video resolution is in excess of 400 dpi (e.g., 500 dpi, 800 dpi, or greater). The user optionally makes contact with touch-sensitive display system  112  using any suitable object or appendage, such as a stylus, a finger, and so forth. In some embodiments, the user interface is designed to work with finger-based contacts and gestures, which can be less precise than stylus-based input due to the larger area of contact of a finger on the touch screen. In some embodiments, the device translates the rough finger-based input into a precise pointer/cursor position or command for performing the actions desired by the user. 
     In some embodiments, in addition to the touch screen, device  100  optionally includes a touchpad (not shown) for activating or deactivating particular functions. In some embodiments, the touchpad is a touch-sensitive area of the device that, unlike the touch screen, does not display visual output. The touchpad is, optionally, a touch-sensitive surface that is separate from touch-sensitive display system  112  or an extension of the touch-sensitive surface formed by the touch screen. 
     Device  100  also includes power system  162  for powering the various components. Power system  162  optionally includes a power management system, one or more power sources (e.g., battery, alternating current (AC)), a recharging system, a power failure detection circuit, a power converter or inverter, a power status indicator (e.g., a light-emitting diode (LED)) and any other components associated with the generation, management and distribution of power in portable devices. 
     Device  100  optionally also includes one or more optical sensors  164 .  FIG. 1A  shows an optical sensor coupled with optical sensor controller  158  in I/O subsystem  106 . Optical sensor(s)  164  optionally include charge-coupled device (CCD) or complementary metal-oxide semiconductor (CMOS) phototransistors. Optical sensor(s)  164  receive light from the environment, projected through one or more lens, and converts the light to data representing an image. In conjunction with imaging module  143  (also called a camera module), optical sensor(s)  164  optionally capture still images and/or video. In some embodiments, an optical sensor is located on the back of device  100 , opposite touch-sensitive display system  112  on the front of the device, so that the touch screen is enabled for use as a viewfinder for still and/or video image acquisition. In some embodiments, another optical sensor is located on the front of the device so that the user&#39;s image is obtained (e.g., for selfies, for videoconferencing while the user views the other video conference participants on the touch screen, etc.). 
     Device  100  optionally also includes one or more contact intensity sensors  165 .  FIG. 1A  shows a contact intensity sensor coupled with intensity sensor controller  159  in I/O subsystem  106 . Contact intensity sensor(s)  165  optionally include one or more piezoresistive strain gauges, capacitive force sensors, electric force sensors, piezoelectric force sensors, optical force sensors, capacitive touch-sensitive surfaces, or other intensity sensors (e.g., sensors used to measure the force (or pressure) of a contact on a touch-sensitive surface). Contact intensity sensor(s)  165  receive contact intensity information (e.g., pressure information or a proxy for pressure information) from the environment. In some embodiments, at least one contact intensity sensor is collocated with, or proximate to, a touch-sensitive surface (e.g., touch-sensitive display system  112 ). In some embodiments, at least one contact intensity sensor is located on the back of device  100 , opposite touch-screen display system  112  which is located on the front of device  100 . 
     Device  100  optionally also includes one or more proximity sensors  166 .  FIG. 1A  shows proximity sensor  166  coupled with peripherals interface  118 . Alternately, proximity sensor  166  is coupled with input controller  160  in I/O subsystem  106 . In some embodiments, the proximity sensor turns off and disables touch-sensitive display system  112  when the multifunction device is placed near the user&#39;s ear (e.g., when the user is making a phone call). 
     Device  100  optionally also includes one or more tactile output generators  167 .  FIG. 1A  shows a tactile output generator coupled with haptic feedback controller  161  in I/O subsystem  106 . Tactile output generator(s)  167  optionally include one or more electroacoustic devices such as speakers or other audio components and/or electromechanical devices that convert energy into linear motion such as a motor, solenoid, electroactive polymer, piezoelectric actuator, electrostatic actuator, or other tactile output generating component (e.g., a component that converts electrical signals into tactile outputs on the device). Tactile output generator(s)  167  receive tactile feedback generation instructions from haptic feedback module  133  and generates tactile outputs on device  100  that are capable of being sensed by a user of device  100 . In some embodiments, at least one tactile output generator is collocated with, or proximate to, a touch-sensitive surface (e.g., touch-sensitive display system  112 ) and, optionally, generates a tactile output by moving the touch-sensitive surface vertically (e.g., in/out of a surface of device  100 ) or laterally (e.g., back and forth in the same plane as a surface of device  100 ). In some embodiments, at least one tactile output generator sensor is located on the back of device  100 , opposite touch-sensitive display system  112 , which is located on the front of device  100 . 
     Device  100  optionally also includes one or more accelerometers  168 .  FIG. 1A  shows accelerometer  168  coupled with peripherals interface  118 . Alternately, accelerometer  168  is, optionally, coupled with an input controller  160  in I/O subsystem  106 . In some embodiments, information is displayed on the touch-screen display in a portrait view or a landscape view based on an analysis of data received from the one or more accelerometers. Device  100  optionally includes, in addition to accelerometer(s)  168 , a magnetometer (not shown) and a GPS (or GLONASS or other global navigation system) receiver (not shown) for obtaining information concerning the location and orientation (e.g., portrait or landscape) of device  100 . 
     In some embodiments, the software components stored in memory  102  include operating system  126 , communication module (or set of instructions)  128 , contact/motion module (or set of instructions)  130 , graphics module (or set of instructions)  132 , haptic feedback module (or set of instructions)  133 , text input module (or set of instructions)  134 , Global Positioning System (GPS) module (or set of instructions)  135 , and applications (or sets of instructions)  136 . Furthermore, in some embodiments, memory  102  stores device/global internal state  157 , as shown in  FIGS. 1A and 3 . Device/global internal state  157  includes one or more of: active application state, indicating which applications, if any, are currently active; display state, indicating what applications, views or other information occupy various regions of touch-sensitive display system  112 ; sensor state, including information obtained from the device&#39;s various sensors and other input or control devices  116 ; and location and/or positional information concerning the device&#39;s location and/or attitude. 
     Operating system  126  (e.g., iOS, Darwin, RTXC, LINUX, UNIX, OS X, WINDOWS, or an embedded operating system such as VxWorks) includes various software components and/or drivers for controlling and managing general system tasks (e.g., memory management, storage device control, power management, etc.) and facilitates communication between various hardware and software components. 
     Communication module  128  facilitates communication with other devices over one or more external ports  124  and also includes various software components for handling data received by RF circuitry  108  and/or external port  124 . External port  124  (e.g., Universal Serial Bus (USB), FIREWIRE, etc.) is adapted for coupling directly to other devices or indirectly over a network (e.g., the Internet, wireless LAN, etc.). In some embodiments, the external port is a multi-pin (e.g., 30-pin) connector that is the same as, or similar to and/or compatible with the 30-pin connector used in some iPhone®, iPod Touch®, and iPad® devices from Apple Inc. of Cupertino, Calif. In some embodiments, the external port is a Lightning connector that is the same as, or similar to and/or compatible with the Lightning connector used in some iPhone®, iPod Touch®, and iPad® devices from Apple Inc. of Cupertino, Calif. 
     Contact/motion module  130  optionally detects contact with touch-sensitive display system  112  (in conjunction with display controller  156 ) and other touch-sensitive devices (e.g., a touchpad or physical click wheel). Contact/motion module  130  includes various software components for performing various operations related to detection of contact (e.g., by a finger or by a stylus), such as determining if contact has occurred (e.g., detecting a finger-down event), determining an intensity of the contact (e.g., the force or pressure of the contact or a substitute for the force or pressure of the contact), determining if there is movement of the contact and tracking the movement across the touch-sensitive surface (e.g., detecting one or more finger-dragging events), and determining if the contact has ceased (e.g., detecting a finger-up event or a break in contact). Contact/motion module  130  receives contact data from the touch-sensitive surface. Determining movement of the point of contact, which is represented by a series of contact data, optionally includes determining speed (magnitude), velocity (magnitude and direction), and/or an acceleration (a change in magnitude and/or direction) of the point of contact. These operations are, optionally, applied to single contacts (e.g., one finger contacts or stylus contacts) or to multiple simultaneous contacts (e.g., “multitouch”/multiple finger contacts). In some embodiments, contact/motion module  130  and display controller  156  detect contact on a touchpad. 
     Contact/motion module  130  optionally detects a gesture input by a user. Different gestures on the touch-sensitive surface have different contact patterns (e.g., different motions, timings, and/or intensities of detected contacts). Thus, a gesture is, optionally, detected by detecting a particular contact pattern. For example, detecting a finger tap gesture includes detecting a finger-down event followed by detecting a finger-up (lift off) event at the same position (or substantially the same position) as the finger-down event (e.g., at the position of an icon). As another example, detecting a finger swipe gesture on the touch-sensitive surface includes detecting a finger-down event followed by detecting one or more finger-dragging events, and subsequently followed by detecting a finger-up (lift off) event. Similarly, tap, swipe, drag, and other gestures are optionally detected for a stylus by detecting a particular contact pattern for the stylus. 
     Graphics module  132  includes various known software components for rendering and displaying graphics on touch-sensitive display system  112  or other display, including components for changing the visual impact (e.g., brightness, transparency, saturation, contrast or other visual property) of graphics that are displayed. As used herein, the term “graphics” includes any object that can be displayed to a user, including without limitation text, web pages, icons (such as user-interface objects including soft keys), digital images, videos, animations and the like. 
     In some embodiments, graphics module  132  stores data representing graphics to be used. Each graphic is, optionally, assigned a corresponding code. Graphics module  132  receives, from applications etc., one or more codes specifying graphics to be displayed along with, if necessary, coordinate data and other graphic property data, and then generates screen image data to output to display controller  156 . 
     Haptic feedback module  133  includes various software components for generating instructions used by tactile output generator(s)  167  to produce tactile outputs at one or more locations on device  100  in response to user interactions with device  100 . 
     Text input module  134 , which is, optionally, a component of graphics module  132 , provides soft keyboards for entering text in various applications (e.g., contacts  137 , e-mail  140 , IM  141 , browser  147 , and any other application that needs text input). 
     GPS module  135  determines the location of the device and provides this information for use in various applications (e.g., to telephone  138  for use in location-based dialing, to camera  143  as picture/video metadata, and to applications that provide location-based services such as weather widgets, local yellow page widgets, and map/navigation widgets). 
     Applications  136  optionally include the following modules (or sets of instructions), or a subset or superset thereof:
         contacts module  137  (sometimes called an address book or contact list);   telephone module  138 ;   video conferencing module  139 ;   e-mail client module  140 ;   instant messaging (IM) module  141 ;   workout support module  142 ;   camera module  143  for still and/or video images;   image management module  144 ;   browser module  147 ;   calendar module  148 ;   widget modules  149 , which optionally include one or more of: weather widget  149 - 1 , stocks widget  149 - 2 , calculator widget  149 - 3 , alarm clock widget  149 - 4 , dictionary widget  149 - 5 , and other widgets obtained by the user, as well as user-created widgets  149 - 6 ;   widget creator module  150  for making user-created widgets  149 - 6 ;   search module  151 ;   video and music player module  152 , which is, optionally, made up of a video player module and a music player module;   notes module  153 ;   map module  154 ; and/or   online video module  155 .       

     Examples of other applications  136  that are, optionally, stored in memory  102  include other word processing applications, other image editing applications, drawing applications, presentation applications, JAVA-enabled applications, encryption, digital rights management, voice recognition, and voice replication. 
     In conjunction with touch-sensitive display system  112 , display controller  156 , contact module  130 , graphics module  132 , and text input module  134 , contacts module  137  includes executable instructions to manage an address book or contact list (e.g., stored in application internal state  192  of contacts module  137  in memory  102  or memory  370 ), including: adding name(s) to the address book; deleting name(s) from the address book; associating telephone number(s), e-mail address(es), physical address(es) or other information with a name; associating an image with a name; categorizing and sorting names; providing telephone numbers and/or e-mail addresses to initiate and/or facilitate communications by telephone  138 , video conference  139 , e-mail  140 , or IM  141 ; and so forth. 
     In conjunction with RF circuitry  108 , audio circuitry  110 , speaker  111 , microphone  113 , touch-sensitive display system  112 , display controller  156 , contact module  130 , graphics module  132 , and text input module  134 , telephone module  138  includes executable instructions to enter a sequence of characters corresponding to a telephone number, access one or more telephone numbers in address book  137 , modify a telephone number that has been entered, dial a respective telephone number, conduct a conversation and disconnect or hang up when the conversation is completed. As noted above, the wireless communication optionally uses any of a plurality of communications standards, protocols and technologies. 
     In conjunction with RF circuitry  108 , audio circuitry  110 , speaker  111 , microphone  113 , touch-sensitive display system  112 , display controller  156 , optical sensor(s)  164 , optical sensor controller  158 , contact module  130 , graphics module  132 , text input module  134 , contact list  137 , and telephone module  138 , videoconferencing module  139  includes executable instructions to initiate, conduct, and terminate a video conference between a user and one or more other participants in accordance with user instructions. 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display controller  156 , contact module  130 , graphics module  132 , and text input module  134 , e-mail client module  140  includes executable instructions to create, send, receive, and manage e-mail in response to user instructions. In conjunction with image management module  144 , e-mail client module  140  makes it very easy to create and send e-mails with still or video images taken with camera module  143 . 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display controller  156 , contact module  130 , graphics module  132 , and text input module  134 , the instant messaging module  141  includes executable instructions to enter a sequence of characters corresponding to an instant message, to modify previously entered characters, to transmit a respective instant message (for example, using a Short Message Service (SMS) or Multimedia Message Service (MMS) protocol for telephony-based instant messages or using XMPP, SIMPLE, Apple Push Notification Service (APNs) or IMPS for Internet-based instant messages), to receive instant messages and to view received instant messages. In some embodiments, transmitted and/or received instant messages optionally include graphics, photos, audio files, video files and/or other attachments as are supported in a MMS and/or an Enhanced Messaging Service (EMS). As used herein, “instant messaging” refers to both telephony-based messages (e.g., messages sent using SMS or MMS) and Internet-based messages (e.g., messages sent using XMPP, SIMPLE, APNs, or IMPS). 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display controller  156 , contact module  130 , graphics module  132 , text input module  134 , GPS module  135 , map module  154 , and music player module  146 , workout support module  142  includes executable instructions to create workouts (e.g., with time, distance, and/or calorie burning goals); communicate with workout sensors (in sports devices and smart watches); receive workout sensor data; calibrate sensors used to monitor a workout; select and play music for a workout; and display, store and transmit workout data. 
     In conjunction with touch-sensitive display system  112 , display controller  156 , optical sensor(s)  164 , optical sensor controller  158 , contact module  130 , graphics module  132 , and image management module  144 , camera module  143  includes executable instructions to capture still images or video (including a video stream) and store them into memory  102 , modify characteristics of a still image or video, and/or delete a still image or video from memory  102 . 
     In conjunction with touch-sensitive display system  112 , display controller  156 , contact module  130 , graphics module  132 , text input module  134 , and camera module  143 , image management module  144  includes executable instructions to arrange, modify (e.g., edit), or otherwise manipulate, label, delete, present (e.g., in a digital slide show or album), and store still and/or video images. 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , and text input module  134 , browser module  147  includes executable instructions to browse the Internet in accordance with user instructions, including searching, linking to, receiving, and displaying web pages or portions thereof, as well as attachments and other files linked to web pages. 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , text input module  134 , e-mail client module  140 , and browser module  147 , calendar module  148  includes executable instructions to create, display, modify, and store calendars and data associated with calendars (e.g., calendar entries, to do lists, etc.) in accordance with user instructions. 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , text input module  134 , and browser module  147 , widget modules  149  are mini-applications that are, optionally, downloaded and used by a user (e.g., weather widget  149 - 1 , stocks widget  149 - 2 , calculator widget  149 - 3 , alarm clock widget  149 - 4 , and dictionary widget  149 - 5 ) or created by the user (e.g., user-created widget  149 - 6 ). In some embodiments, a widget includes an HTML (Hypertext Markup Language) file, a CSS (Cascading Style Sheets) file, and a JavaScript file. In some embodiments, a widget includes an XML (Extensible Markup Language) file and a JavaScript file (e.g., Yahoo! Widgets). 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , text input module  134 , and browser module  147 , the widget creator module  150  includes executable instructions to create widgets (e.g., turning a user-specified portion of a web page into a widget). 
     In conjunction with touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , and text input module  134 , search module  151  includes executable instructions to search for text, music, sound, image, video, and/or other files in memory  102  that match one or more search criteria (e.g., one or more user-specified search terms) in accordance with user instructions. 
     In conjunction with touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , audio circuitry  110 , speaker  111 , RF circuitry  108 , and browser module  147 , video and music player module  152  includes executable instructions that allow the user to download and play back recorded music and other sound files stored in one or more file formats, such as MP3 or AAC files, and executable instructions to display, present or otherwise play back videos (e.g., on touch-sensitive display system  112 , or on an external display connected wirelessly or via external port  124 ). In some embodiments, device  100  optionally includes the functionality of an MP3 player, such as an iPod (trademark of Apple Inc.). 
     In conjunction with touch-sensitive display system  112 , display controller  156 , contact module  130 , graphics module  132 , and text input module  134 , notes module  153  includes executable instructions to create and manage notes, to do lists, and the like in accordance with user instructions. 
     In conjunction with RF circuitry  108 , touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , text input module  134 , GPS module  135 , and browser module  147 , map module  154  includes executable instructions to receive, display, modify, and store maps and data associated with maps (e.g., driving directions; data on stores and other points of interest at or near a particular location; and other location-based data) in accordance with user instructions. 
     In conjunction with touch-sensitive display system  112 , display system controller  156 , contact module  130 , graphics module  132 , audio circuitry  110 , speaker  111 , RF circuitry  108 , text input module  134 , e-mail client module  140 , and browser module  147 , online video module  155  includes executable instructions that allow the user to access, browse, receive (e.g., by streaming and/or download), play back (e.g., on the touch screen  112 , or on an external display connected wirelessly or via external port  124 ), send an e-mail with a link to a particular online video, and otherwise manage online videos in one or more file formats, such as H.264. In some embodiments, instant messaging module  141 , rather than e-mail client module  140 , is used to send a link to a particular online video. 
     Each of the above identified modules and applications correspond to a set of executable instructions for performing one or more functions described above and the methods described in this application (e.g., the computer-implemented methods and other information processing methods described herein). These modules (i.e., sets of instructions) need not be implemented as separate software programs, procedures or modules, and thus various subsets of these modules are, optionally, combined or otherwise re-arranged in various embodiments. In some embodiments, memory  102  optionally stores a subset of the modules and data structures identified above. Furthermore, memory  102  optionally stores additional modules and data structures not described above. 
     In some embodiments, device  100  is a device where operation of a predefined set of functions on the device is performed exclusively through a touch screen and/or a touchpad. By using a touch screen and/or a touchpad as the primary input control device for operation of device  100 , the number of physical input control devices (such as push buttons, dials, and the like) on device  100  is, optionally, reduced. 
     The predefined set of functions that are performed exclusively through a touch screen and/or a touchpad optionally include navigation between user interfaces. In some embodiments, the touchpad, when touched by the user, navigates device  100  to a main, home, or root menu from any user interface that is displayed on device  100 . In such embodiments, a “menu button” is implemented using a touchpad. In some other embodiments, the menu button is a physical push button or other physical input control device instead of a touchpad. 
       FIG. 1B  is a block diagram illustrating exemplary components for event handling in accordance with some embodiments. In some embodiments, memory  102  (in  FIG. 1A ) or  370  ( FIG. 3 ) includes event sorter  170  (e.g., in operating system  126 ) and a respective application  136 - 1  (e.g., any of the aforementioned applications  136 ,  137 - 155 ,  380 - 390 ). 
     Event sorter  170  receives event information and determines the application  136 - 1  and application view  191  of application  136 - 1  to which to deliver the event information. Event sorter  170  includes event monitor  171  and event dispatcher module  174 . In some embodiments, application  136 - 1  includes application internal state  192 , which indicates the current application view(s) displayed on touch-sensitive display system  112  when the application is active or executing. In some embodiments, device/global internal state  157  is used by event sorter  170  to determine which application(s) is (are) currently active, and application internal state  192  is used by event sorter  170  to determine application views  191  to which to deliver event information. 
     In some embodiments, application internal state  192  includes additional information, such as one or more of: resume information to be used when application  136 - 1  resumes execution, user interface state information that indicates information being displayed or that is ready for display by application  136 - 1 , a state queue for enabling the user to go back to a prior state or view of application  136 - 1 , and a redo/undo queue of previous actions taken by the user. 
     Event monitor  171  receives event information from peripherals interface  118 . Event information includes information about a sub-event (e.g., a user touch on touch-sensitive display system  112 , as part of a multi-touch gesture). Peripherals interface  118  transmits information it receives from I/O subsystem  106  or a sensor, such as proximity sensor  166 , accelerometer(s)  168 , and/or microphone  113  (through audio circuitry  110 ). Information that peripherals interface  118  receives from I/O subsystem  106  includes information from touch-sensitive display system  112  or a touch-sensitive surface. 
     In some embodiments, event monitor  171  sends requests to the peripherals interface  118  at predetermined intervals. In response, peripherals interface  118  transmits event information. In other embodiments, peripheral interface  118  transmits event information only when there is a significant event (e.g., receiving an input above a predetermined noise threshold and/or for more than a predetermined duration). 
     In some embodiments, event sorter  170  also includes a hit view determination module  172  and/or an active event recognizer determination module  173 . 
     Hit view determination module  172  provides software procedures for determining where a sub-event has taken place within one or more views, when touch-sensitive display system  112  displays more than one view. Views are made up of controls and other elements that a user can see on the display. 
     Another aspect of the user interface associated with an application is a set of views, sometimes herein called application views or user interface windows, in which information is displayed and touch-based gestures occur. The application views (of a respective application) in which a touch is detected optionally correspond to programmatic levels within a programmatic or view hierarchy of the application. For example, the lowest level view in which a touch is detected is, optionally, called the hit view, and the set of events that are recognized as proper inputs are, optionally, determined based, at least in part, on the hit view of the initial touch that begins a touch-based gesture. 
     Hit view determination module  172  receives information related to sub-events of a touch-based gesture. When an application has multiple views organized in a hierarchy, hit view determination module  172  identifies a hit view as the lowest view in the hierarchy which should handle the sub-event. In most circumstances, the hit view is the lowest level view in which an initiating sub-event occurs (i.e., the first sub-event in the sequence of sub-events that form an event or potential event). Once the hit view is identified by the hit view determination module, the hit view typically receives all sub-events related to the same touch or input source for which it was identified as the hit view. 
     Active event recognizer determination module  173  determines which view or views within a view hierarchy should receive a particular sequence of sub-events. In some embodiments, active event recognizer determination module  173  determines that only the hit view should receive a particular sequence of sub-events. In other embodiments, active event recognizer determination module  173  determines that all views that include the physical location of a sub-event are actively involved views, and therefore determines that all actively involved views should receive a particular sequence of sub-events. In other embodiments, even if touch sub-events were entirely confined to the area associated with one particular view, views higher in the hierarchy would still remain as actively involved views. 
     Event dispatcher module  174  dispatches the event information to an event recognizer (e.g., event recognizer  180 ). In embodiments including active event recognizer determination module  173 , event dispatcher module  174  delivers the event information to an event recognizer determined by active event recognizer determination module  173 . In some embodiments, event dispatcher module  174  stores in an event queue the event information, which is retrieved by a respective event receiver module  182 . 
     In some embodiments, operating system  126  includes event sorter  170 . Alternatively, application  136 - 1  includes event sorter  170 . In yet other embodiments, event sorter  170  is a stand-alone module, or a part of another module stored in memory  102 , such as contact/motion module  130 . 
     In some embodiments, application  136 - 1  includes a plurality of event handlers  190  and one or more application views  191 , each of which includes instructions for handling touch events that occur within a respective view of the application&#39;s user interface. Each application view  191  of the application  136 - 1  includes one or more event recognizers  180 . Typically, a respective application view  191  includes a plurality of event recognizers  180 . In other embodiments, one or more of event recognizers  180  are part of a separate module, such as a user interface kit (not shown) or a higher level object from which application  136 - 1  inherits methods and other properties. In some embodiments, a respective event handler  190  includes one or more of: data updater  176 , object updater  177 , GUI updater  178 , and/or event data  179  received from event sorter  170 . Event handler  190  optionally utilizes or calls data updater  176 , object updater  177  or GUI updater  178  to update the application internal state  192 . Alternatively, one or more of the application views  191  includes one or more respective event handlers  190 . Also, in some embodiments, one or more of data updater  176 , object updater  177 , and GUI updater  178  are included in a respective application view  191 . 
     A respective event recognizer  180  receives event information (e.g., event data  179 ) from event sorter  170 , and identifies an event from the event information. Event recognizer  180  includes event receiver  182  and event comparator  184 . In some embodiments, event recognizer  180  also includes at least a subset of: metadata  183 , and event delivery instructions  188  (which optionally include sub-event delivery instructions). 
     Event receiver  182  receives event information from event sorter  170 . The event information includes information about a sub-event, for example, a touch or a touch movement. Depending on the sub-event, the event information also includes additional information, such as location of the sub-event. When the sub-event concerns motion of a touch, the event information optionally also includes speed and direction of the sub-event. In some embodiments, events include rotation of the device from one orientation to another (e.g., from a portrait orientation to a landscape orientation, or vice versa), and the event information includes corresponding information about the current orientation (also called device attitude) of the device. 
     Event comparator  184  compares the event information to predefined event or sub-event definitions and, based on the comparison, determines an event or sub-event, or determines or updates the state of an event or sub-event. In some embodiments, event comparator  184  includes event definitions  186 . Event definitions  186  contain definitions of events (e.g., predefined sequences of sub-events), for example, event  1  ( 187 - 1 ), event  2  ( 187 - 2 ), and others. In some embodiments, sub-events in an event  187  include, for example, touch begin, touch end, touch movement, touch cancellation, and multiple touching. In one example, the definition for event  1  ( 187 - 1 ) is a double tap on a displayed object. The double tap, for example, comprises a first touch (touch begin) on the displayed object for a predetermined phase, a first lift-off (touch end) for a predetermined phase, a second touch (touch begin) on the displayed object for a predetermined phase, and a second lift-off (touch end) for a predetermined phase. In another example, the definition for event  2  ( 187 - 2 ) is a dragging on a displayed object. The dragging, for example, comprises a touch (or contact) on the displayed object for a predetermined phase, a movement of the touch across touch-sensitive display system  112 , and lift-off of the touch (touch end). In some embodiments, the event also includes information for one or more associated event handlers  190 . 
     In some embodiments, event definition  187  includes a definition of an event for a respective user-interface object. In some embodiments, event comparator  184  performs a hit test to determine which user-interface object is associated with a sub-event. For example, in an application view in which three user-interface objects are displayed on touch-sensitive display system  112 , when a touch is detected on touch-sensitive display system  112 , event comparator  184  performs a hit test to determine which of the three user-interface objects is associated with the touch (sub-event). If each displayed object is associated with a respective event handler  190 , the event comparator uses the result of the hit test to determine which event handler  190  should be activated. For example, event comparator  184  selects an event handler associated with the sub-event and the object triggering the hit test. 
     In some embodiments, the definition for a respective event  187  also includes delayed actions that delay delivery of the event information until after it has been determined whether the sequence of sub-events does or does not correspond to the event recognizer&#39;s event type. 
     When a respective event recognizer  180  determines that the series of sub-events do not match any of the events in event definitions  186 , the respective event recognizer  180  enters an event impossible, event failed, or event ended state, after which it disregards subsequent sub-events of the touch-based gesture. In this situation, other event recognizers, if any, that remain active for the hit view continue to track and process sub-events of an ongoing touch-based gesture. 
     In some embodiments, a respective event recognizer  180  includes metadata  183  with configurable properties, flags, and/or lists that indicate how the event delivery system should perform sub-event delivery to actively involved event recognizers. In some embodiments, metadata  183  includes configurable properties, flags, and/or lists that indicate how event recognizers interact, or are enabled to interact, with one another. In some embodiments, metadata  183  includes configurable properties, flags, and/or lists that indicate whether sub-events are delivered to varying levels in the view or programmatic hierarchy. 
     In some embodiments, a respective event recognizer  180  activates event handler  190  associated with an event when one or more particular sub-events of an event are recognized. In some embodiments, a respective event recognizer  180  delivers event information associated with the event to event handler  190 . Activating an event handler  190  is distinct from sending (and deferred sending) sub-events to a respective hit view. In some embodiments, event recognizer  180  throws a flag associated with the recognized event, and event handler  190  associated with the flag catches the flag and performs a predefined process. 
     In some embodiments, event delivery instructions  188  include sub-event delivery instructions that deliver event information about a sub-event without activating an event handler. Instead, the sub-event delivery instructions deliver event information to event handlers associated with the series of sub-events or to actively involved views. Event handlers associated with the series of sub-events or with actively involved views receive the event information and perform a predetermined process. 
     In some embodiments, data updater  176  creates and updates data used in application  136 - 1 . For example, data updater  176  updates the telephone number used in contacts module  137 , or stores a video file used in video player module  145 . In some embodiments, object updater  177  creates and updates objects used in application  136 - 1 . For example, object updater  177  creates a new user-interface object or updates the position of a user-interface object. GUI updater  178  updates the GUI. For example, GUI updater  178  prepares display information and sends it to graphics module  132  for display on a touch-sensitive display. 
     In some embodiments, event handler(s)  190  includes or has access to data updater  176 , object updater  177 , and GUI updater  178 . In some embodiments, data updater  176 , object updater  177 , and GUI updater  178  are included in a single module of a respective application  136 - 1  or application view  191 . In other embodiments, they are included in two or more software modules. 
     It shall be understood that the foregoing discussion regarding event handling of user touches on touch-sensitive displays also applies to other forms of user inputs to operate multifunction devices  100  with input-devices, not all of which are initiated on touch screens. For example, mouse movement and mouse button presses, optionally coordinated with single or multiple keyboard presses or holds; contact movements such as taps, drags, scrolls, etc., on touch-pads; pen stylus inputs; movement of the device; oral instructions; detected eye movements; biometric inputs; and/or any combination thereof are optionally utilized as inputs corresponding to sub-events which define an event to be recognized. 
       FIG. 2  illustrates a portable multifunction device  100  having a touch screen (e.g., touch-sensitive display system  112 ,  FIG. 1A ) in accordance with some embodiments. The touch screen optionally displays one or more graphics within user interface (UI)  200 . In this embodiment, as well as others described below, a user is enabled to select one or more of the graphics by making a gesture on the graphics, for example, with one or more fingers  202  (not drawn to scale in the figure) or one or more styluses  203  (not drawn to scale in the figure). In some embodiments, selection of one or more graphics occurs when the user breaks contact with the one or more graphics. In some embodiments, the gesture optionally includes one or more taps, one or more swipes (from left to right, right to left, upward and/or downward) and/or a rolling of a finger (from right to left, left to right, upward and/or downward) that has made contact with device  100 . In some implementations or circumstances, inadvertent contact with a graphic does not select the graphic. For example, a swipe gesture that sweeps over an application icon optionally does not select the corresponding application when the gesture corresponding to selection is a tap. 
     Device  100  optionally also includes one or more physical buttons, such as “home” or menu button  204 . As described previously, menu button  204  is, optionally, used to navigate to any application  136  in a set of applications that are, optionally executed on device  100 . Alternatively, in some embodiments, the menu button is implemented as a soft key in a GUI displayed on the touch-screen display. 
     In some embodiments, device  100  includes the touch-screen display, menu button  204 , push button  206  for powering the device on/off and locking the device, volume adjustment button(s)  208 , Subscriber Identity Module (SIM) card slot  210 , head set jack  212 , and docking/charging external port  124 . Push button  206  is, optionally, used to turn the power on/off on the device by depressing the button and holding the button in the depressed state for a predefined time interval; to lock the device by depressing the button and releasing the button before the predefined time interval has elapsed; and/or to unlock the device or initiate an unlock process. In some embodiments, device  100  also accepts verbal input for activation or deactivation of some functions through microphone  113 . Device  100  also, optionally, includes one or more contact intensity sensors  165  for detecting intensity of contacts on touch-sensitive display system  112  and/or one or more tactile output generators  167  for generating tactile outputs for a user of device  100 . 
       FIG. 3  is a block diagram of an exemplary multifunction device with a display and a touch-sensitive surface in accordance with some embodiments. Device  300  need not be portable. In some embodiments, device  300  is a laptop computer, a desktop computer, a tablet computer, a multimedia player device, a navigation device, an educational device (such as a child&#39;s learning toy), a gaming system, or a control device (e.g., a home or industrial controller). Device  300  typically includes one or more processing units (CPUs)  310 , one or more network or other communications interfaces  360 , memory  370 , and one or more communication buses  320  for interconnecting these components. Communication buses  320  optionally include circuitry (sometimes called a chipset) that interconnects and controls communications between system components. Device  300  includes input/output (I/O) interface  330  comprising display  340 , which is typically a touch-screen display. I/O interface  330  also optionally includes a keyboard and/or mouse (or other pointing device)  350  and touchpad  355 , tactile output generator  357  for generating tactile outputs on device  300  (e.g., similar to tactile output generator(s)  167  described above with reference to  FIG. 1A ), sensors  359  (e.g., optical, acceleration, proximity, touch-sensitive, and/or contact intensity sensors similar to contact intensity sensor(s)  165  described above with reference to  FIG. 1A ). Memory  370  includes high-speed random access memory, such as DRAM, SRAM, DDR RAM or other random access solid state memory devices; and optionally includes non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid state storage devices. Memory  370  optionally includes one or more storage devices remotely located from CPU(s)  310 . In some embodiments, memory  370  stores programs, modules, and data structures analogous to the programs, modules, and data structures stored in memory  102  of portable multifunction device  100  ( FIG. 1A ), or a subset thereof. Furthermore, memory  370  optionally stores additional programs, modules, and data structures not present in memory  102  of portable multifunction device  100 . For example, memory  370  of device  300  optionally stores drawing module  380 , presentation module  382 , word processing module  384 , website creation module  386 , disk authoring module  388 , and/or spreadsheet module  390 , while memory  102  of portable multifunction device  100  ( FIG. 1A ) optionally does not store these modules. 
     Each of the above identified elements in  FIG. 3  are, optionally, stored in one or more of the previously mentioned memory devices. Each of the above identified modules corresponds to a set of instructions for performing a function described above. The above identified modules or programs (i.e., sets of instructions) need not be implemented as separate software programs, procedures or modules, and thus various subsets of these modules are, optionally, combined or otherwise re-arranged in various embodiments. In some embodiments, memory  370  optionally stores a subset of the modules and data structures identified above. Furthermore, memory  370  optionally stores additional modules and data structures not described above. 
     Attention is now directed towards embodiments of user interfaces (“UI”) that are, optionally, implemented on portable multifunction device  100 . 
       FIG. 4A  illustrates an exemplary user interface for a menu of applications on portable multifunction device  100  in accordance with some embodiments. Similar user interfaces are, optionally, implemented on device  300 . In some embodiments, user interface  400  includes the following elements, or a subset or superset thereof:
         Signal strength indicator(s)  402  for wireless communication(s), such as cellular and Wi-Fi signals;   Time  404 ;   Bluetooth indicator  405 ;   Battery status indicator  406 ;   Tray  408  with icons for frequently used applications, such as:
           Icon  416  for telephone module  138 , labeled “Phone,” which optionally includes an indicator  414  of the number of missed calls or voicemail messages;   Icon  418  for e-mail client module  140 , labeled “Mail,” which optionally includes an indicator  410  of the number of unread e-mails;   Icon  420  for browser module  147 , labeled “Browser;” and   Icon  422  for video and music player module  152 , also referred to as iPod (trademark of Apple Inc.) module  152 , labeled “iPod;” and   
           Icons for other applications, such as:
           Icon  424  for IM module  141 , labeled “Messages;”   Icon  426  for calendar module  148 , labeled “Calendar;”   Icon  428  for image management module  144 , labeled “Photos;”   Icon  430  for camera module  143 , labeled “Camera;”   Icon  432  for online video module  155 , labeled “Online Video;”   Icon  434  for stocks widget  149 - 2 , labeled “Stocks;”   Icon  436  for map module  154 , labeled “Map;”   Icon  438  for weather widget  149 - 1 , labeled “Weather;”   Icon  440  for alarm clock widget  149 - 4 , labeled “Clock;”   Icon  442  for workout support module  142 , labeled “Workout Support;”   Icon  444  for notes module  153 , labeled “Notes;” and   Icon  446  for a settings application or module, which provides access to settings for device  100  and its various applications  136 .   
               

     It should be noted that the icon labels illustrated in  FIG. 4A  are merely exemplary. For example, in some embodiments, icon  422  for video and music player module  152  is labeled “Music” or “Music Player.” Other labels are, optionally, used for various application icons. In some embodiments, a label for a respective application icon includes a name of an application corresponding to the respective application icon. In some embodiments, a label for a particular application icon is distinct from a name of an application corresponding to the particular application icon. 
       FIG. 4B  illustrates an exemplary user interface on a device (e.g., device  300 ,  FIG. 3 ) with a touch-sensitive surface  451  (e.g., a tablet or touchpad  355 ,  FIG. 3 ) that is separate from the display  450 . Device  300  also, optionally, includes one or more contact intensity sensors (e.g., one or more of sensors  357 ) for detecting intensity of contacts on touch-sensitive surface  451  and/or one or more tactile output generators  359  for generating tactile outputs for a user of device  300 . 
       FIG. 4B  illustrates an exemplary user interface on a device (e.g., device  300 ,  FIG. 3 ) with a touch-sensitive surface  451  (e.g., a tablet or touchpad  355 ,  FIG. 3 ) that is separate from the display  450 . Although many of the examples that follow will be given with reference to inputs on touch screen display  112  (where the touch sensitive surface and the display are combined), in some embodiments, the device detects inputs on a touch-sensitive surface that is separate from the display, as shown in  FIG. 4B . In some embodiments, the touch-sensitive surface (e.g.,  451  in  FIG. 4B ) has a primary axis (e.g.,  452  in  FIG. 4B ) that corresponds to a primary axis (e.g.,  453  in  FIG. 4B ) on the display (e.g.,  450 ). In accordance with these embodiments, the device detects contacts (e.g.,  460  and  462  in  FIG. 4B ) with the touch-sensitive surface  451  at locations that correspond to respective locations on the display (e.g., in  FIG. 4B, 460  corresponds to  468  and  462  corresponds to  470 ). In this way, user inputs (e.g., contacts  460  and  462 , and movements thereof) detected by the device on the touch-sensitive surface (e.g.,  451  in  FIG. 4B ) are used by the device to manipulate the user interface on the display (e.g.,  450  in  FIG. 4B ) of the multifunction device when the touch-sensitive surface is separate from the display. It should be understood that similar methods are, optionally, used for other user interfaces described herein. 
     Additionally, while the following examples are given primarily with reference to finger inputs (e.g., finger contacts, finger tap gestures, finger swipe gestures, etc.), it should be understood that, in some embodiments, one or more of the finger inputs are replaced with input from another input device (e.g., a mouse based input or a stylus input). For example, a swipe gesture is, optionally, replaced with a mouse click (e.g., instead of a contact) followed by movement of the cursor along the path of the swipe (e.g., instead of movement of the contact). As another example, a tap gesture is, optionally, replaced with a mouse click while the cursor is located over the location of the tap gesture (e.g., instead of detection of the contact followed by ceasing to detect the contact). Similarly, when multiple user inputs are simultaneously detected, it should be understood that multiple computer mice are, optionally, used simultaneously, or a mouse and finger contacts are, optionally, used simultaneously. 
     As used herein, the term “focus selector” refers to an input element that indicates a current part of a user interface with which a user is interacting. In some implementations that include a cursor or other location marker, the cursor acts as a “focus selector,” so that when an input (e.g., a press input) is detected on a touch-sensitive surface (e.g., touchpad  355  in  FIG. 3  or touch-sensitive surface  451  in  FIG. 4B ) while the cursor is over a particular user interface element (e.g., a button, window, slider or other user interface element), the particular user interface element is adjusted in accordance with the detected input. In some implementations that include a touch-screen display (e.g., touch-sensitive display system  112  in  FIG. 1A  or the touch screen in  FIG. 4A ) that enables direct interaction with user interface elements on the touch-screen display, a detected contact on the touch-screen acts as a “focus selector,” so that when an input (e.g., a press input by the contact) is detected on the touch-screen display at a location of a particular user interface element (e.g., a button, window, slider or other user interface element), the particular user interface element is adjusted in accordance with the detected input. In some implementations, focus is moved from one region of a user interface to another region of the user interface without corresponding movement of a cursor or movement of a contact on a touch-screen display (e.g., by using a tab key or arrow keys to move focus from one button to another button); in these implementations, the focus selector moves in accordance with movement of focus between different regions of the user interface. Without regard to the specific form taken by the focus selector, the focus selector is generally the user interface element (or contact on a touch-screen display) that is controlled by the user so as to communicate the user&#39;s intended interaction with the user interface (e.g., by indicating, to the device, the element of the user interface with which the user is intending to interact). For example, the location of a focus selector (e.g., a cursor, a contact, or a selection box) over a respective button while a press input is detected on the touch-sensitive surface (e.g., a touchpad or touch screen) will indicate that the user is intending to activate the respective button (as opposed to other user interface elements shown on a display of the device). 
     As used in the specification and claims, the term “intensity” of a contact on a touch-sensitive surface refers to the force or pressure (force per unit area) of a contact (e.g., a finger contact or a stylus contact) on the touch-sensitive surface, or to a substitute (proxy) for the force or pressure of a contact on the touch-sensitive surface. The intensity of a contact has a range of values that includes at least four distinct values and more typically includes hundreds of distinct values (e.g., at least 256). Intensity of a contact is, optionally, determined (or measured) using various approaches and various sensors or combinations of sensors. For example, one or more force sensors underneath or adjacent to the touch-sensitive surface are, optionally, used to measure force at various points on the touch-sensitive surface. In some implementations, force measurements from multiple force sensors are combined (e.g., a weighted average or a sum) to determine an estimated force of a contact. Similarly, a pressure-sensitive tip of a stylus is, optionally, used to determine a pressure of the stylus on the touch-sensitive surface. Alternatively, the size of the contact area detected on the touch-sensitive surface and/or changes thereto, the capacitance of the touch-sensitive surface proximate to the contact and/or changes thereto, and/or the resistance of the touch-sensitive surface proximate to the contact and/or changes thereto are, optionally, used as a substitute for the force or pressure of the contact on the touch-sensitive surface. In some implementations, the substitute measurements for contact force or pressure are used directly to determine whether an intensity threshold has been exceeded (e.g., the intensity threshold is described in units corresponding to the substitute measurements). In some implementations, the substitute measurements for contact force or pressure are converted to an estimated force or pressure and the estimated force or pressure is used to determine whether an intensity threshold has been exceeded (e.g., the intensity threshold is a pressure threshold measured in units of pressure). Using the intensity of a contact as an attribute of a user input allows for user access to additional device functionality that may otherwise not be readily accessible by the user on a reduced-size device with limited real estate for displaying affordances (e.g., on a touch-sensitive display) and/or receiving user input (e.g., via a touch-sensitive display, a touch-sensitive surface, or a physical/mechanical control such as a knob or a button). 
     In some embodiments, contact/motion module  130  uses a set of one or more intensity thresholds to determine whether an operation has been performed by a user (e.g., to determine whether a user has “clicked” on an icon). In some embodiments, at least a subset of the intensity thresholds are determined in accordance with software parameters (e.g., the intensity thresholds are not determined by the activation thresholds of particular physical actuators and can be adjusted without changing the physical hardware of device  100 ). For example, a mouse “click” threshold of a trackpad or touch-screen display can be set to any of a large range of predefined thresholds values without changing the trackpad or touch-screen display hardware. Additionally, in some implementations a user of the device is provided with software settings for adjusting one or more of the set of intensity thresholds (e.g., by adjusting individual intensity thresholds and/or by adjusting a plurality of intensity thresholds at once with a system-level click “intensity” parameter). 
     As used in the specification and claims, the term “characteristic intensity” of a contact refers to a characteristic of the contact based on one or more intensities of the contact. In some embodiments, the characteristic intensity is based on multiple intensity samples. The characteristic intensity is, optionally, based on a predefined number of intensity samples, or a set of intensity samples collected during a predetermined time period (e.g., 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10 seconds) relative to a predefined event (e.g., after detecting the contact, prior to detecting liftoff of the contact, before or after detecting a start of movement of the contact, prior to detecting an end of the contact, before or after detecting an increase in intensity of the contact, and/or before or after detecting a decrease in intensity of the contact). A characteristic intensity of a contact is, optionally based on one or more of: a maximum value of the intensities of the contact, a mean value of the intensities of the contact, an average value of the intensities of the contact, a top 10 percentile value of the intensities of the contact, a value at the half maximum of the intensities of the contact, a value at the 90 percent maximum of the intensities of the contact, or the like. In some embodiments, the duration of the contact is used in determining the characteristic intensity (e.g., when the characteristic intensity is an average of the intensity of the contact over time). In some embodiments, the characteristic intensity is compared to a set of one or more intensity thresholds to determine whether an operation has been performed by a user. For example, the set of one or more intensity thresholds may include a first intensity threshold and a second intensity threshold. In this example, a contact with a characteristic intensity that does not exceed the first threshold results in a first operation, a contact with a characteristic intensity that exceeds the first intensity threshold and does not exceed the second intensity threshold results in a second operation, and a contact with a characteristic intensity that exceeds the second intensity threshold results in a third operation. In some embodiments, a comparison between the characteristic intensity and one or more intensity thresholds is used to determine whether or not to perform one or more operations (e.g., whether to perform a respective option or forgo performing the respective operation) rather than being used to determine whether to perform a first operation or a second operation. 
     In some embodiments, a portion of a gesture is identified for purposes of determining a characteristic intensity. For example, a touch-sensitive surface may receive a continuous swipe contact transitioning from a start location and reaching an end location (e.g., a drag gesture), at which point the intensity of the contact increases. In this example, the characteristic intensity of the contact at the end location may be based on only a portion of the continuous swipe contact, and not the entire swipe contact (e.g., only the portion of the swipe contact at the end location). In some embodiments, a smoothing algorithm may be applied to the intensities of the swipe contact prior to determining the characteristic intensity of the contact. For example, the smoothing algorithm optionally includes one or more of: an unweighted sliding-average smoothing algorithm, a triangular smoothing algorithm, a median filter smoothing algorithm, and/or an exponential smoothing algorithm. In some circumstances, these smoothing algorithms eliminate narrow spikes or dips in the intensities of the swipe contact for purposes of determining a characteristic intensity. 
     The user interface figures described herein optionally include various intensity diagrams that show the current intensity of the contact on the touch-sensitive surface relative to one or more intensity thresholds (e.g., a contact detection intensity threshold IT 0 , a light press intensity threshold IT L , a deep press intensity threshold IT D  (e.g., that is at least initially higher than I L ), and/or one or more other intensity thresholds (e.g., an intensity threshold I H  that is lower than I L )). This intensity diagram is typically not part of the displayed user interface, but is provided to aid in the interpretation of the figures. In some embodiments, the light press intensity threshold corresponds to an intensity at which the device will perform operations typically associated with clicking a button of a physical mouse or a trackpad. In some embodiments, the deep press intensity threshold corresponds to an intensity at which the device will perform operations that are different from operations typically associated with clicking a button of a physical mouse or a trackpad. In some embodiments, when a contact is detected with a characteristic intensity below the light press intensity threshold (e.g., and above a nominal contact-detection intensity threshold IT 0  below which the contact is no longer detected), the device will move a focus selector in accordance with movement of the contact on the touch-sensitive surface without performing an operation associated with the light press intensity threshold or the deep press intensity threshold. Generally, unless otherwise stated, these intensity thresholds are consistent between different sets of user interface figures. 
     In some embodiments, the response of the device to inputs detected by the device depends on criteria based on the contact intensity during the input. For example, for some “light press” inputs, the intensity of a contact exceeding a first intensity threshold during the input triggers a first response. In some embodiments, the response of the device to inputs detected by the device depends on criteria that include both the contact intensity during the input and time-based criteria. For example, for some “deep press” inputs, the intensity of a contact exceeding a second intensity threshold during the input, greater than the first intensity threshold for a light press, triggers a second response only if a delay time has elapsed between meeting the first intensity threshold and meeting the second intensity threshold. This delay time is typically less than 200 ms in duration (e.g., 40, 100, or 120 ms, depending on the magnitude of the second intensity threshold, with the delay time increasing as the second intensity threshold increases). This delay time helps to avoid accidental deep press inputs. As another example, for some “deep press” inputs, there is a reduced-sensitivity time period that occurs after the time at which the first intensity threshold is met. During the reduced-sensitivity time period, the second intensity threshold is increased. This temporary increase in the second intensity threshold also helps to avoid accidental deep press inputs. For other deep press inputs, the response to detection of a deep press input does not depend on time-based criteria. 
     In some embodiments, one or more of the input intensity thresholds and/or the corresponding outputs vary based on one or more factors, such as user settings, contact motion, input timing, application running, rate at which the intensity is applied, number of concurrent inputs, user history, environmental factors (e.g., ambient noise), focus selector position, and the like. Exemplary factors are described in U.S. patent application Ser. Nos. 14/399,606 and 14/624,296, which are incorporated by reference herein in their entireties. 
     For example,  FIG. 4C  illustrates a dynamic intensity threshold  480  that changes over time based in part on the intensity of touch input  476  over time. Dynamic intensity threshold  480  is a sum of two components, first component  474  that decays over time after a predefined delay time p 1  from when touch input  476  is initially detected, and second component  478  that trails the intensity of touch input  476  over time. The initial high intensity threshold of first component  474  reduces accidental triggering of a “deep press” response, while still allowing an immediate “deep press” response if touch input  476  provides sufficient intensity. Second component  478  reduces unintentional triggering of a “deep press” response by gradual intensity fluctuations of in a touch input. In some embodiments, when touch input  476  satisfies dynamic intensity threshold  480  (e.g., at point  481  in  FIG. 4C ), the “deep press” response is triggered. 
       FIG. 4D  illustrates another dynamic intensity threshold  486  (e.g., intensity threshold I D ).  FIG. 4D  also illustrates two other intensity thresholds: a first intensity threshold I H  and a second intensity threshold I L . In  FIG. 4D , although touch input  484  satisfies the first intensity threshold I H  and the second intensity threshold I L  prior to time p 2 , no response is provided until delay time p 2  has elapsed at time  482 . Also in  FIG. 4D , dynamic intensity threshold  486  decays over time, with the decay starting at time  488  after a predefined delay time p 1  has elapsed from time  482  (when the response associated with the second intensity threshold I L  was triggered). This type of dynamic intensity threshold reduces accidental triggering of a response associated with the dynamic intensity threshold I D  immediately after, or concurrently with, triggering a response associated with a lower intensity threshold, such as the first intensity threshold I H  or the second intensity threshold I L . 
       FIG. 4E  illustrate yet another dynamic intensity threshold  492  (e.g., intensity threshold I D ). In  FIG. 4E , a response associated with the intensity threshold I L  is triggered after the delay time p 2  has elapsed from when touch input  490  is initially detected. Concurrently, dynamic intensity threshold  492  decays after the predefined delay time p 1  has elapsed from when touch input  490  is initially detected. So a decrease in intensity of touch input  490  after triggering the response associated with the intensity threshold I L , followed by an increase in the intensity of touch input  490 , without releasing touch input  490 , can trigger a response associated with the intensity threshold I D  (e.g., at time  494 ) even when the intensity of touch input  490  is below another intensity threshold, for example, the intensity threshold I L . 
     An increase of characteristic intensity of the contact from an intensity below the light press intensity threshold IT L  to an intensity between the light press intensity threshold IT L  and the deep press intensity threshold IT D  is sometimes referred to as a “light press” input. An increase of characteristic intensity of the contact from an intensity below the deep press intensity threshold IT D  to an intensity above the deep press intensity threshold IT D  is sometimes referred to as a “deep press” input. An increase of characteristic intensity of the contact from an intensity below the contact-detection intensity threshold IT 0  to an intensity between the contact-detection intensity threshold IT 0  and the light press intensity threshold IT L  is sometimes referred to as detecting the contact on the touch-surface. A decrease of characteristic intensity of the contact from an intensity above the contact-detection intensity threshold IT 0  to an intensity below the contact-detection intensity threshold IT 0  is sometimes referred to as detecting liftoff of the contact from the touch-surface. In some embodiments IT 0  is zero. In some embodiments, IT 0  is greater than zero. In some illustrations a shaded circle or oval is used to represent intensity of a contact on the touch-sensitive surface. In some illustrations, a circle or oval without shading is used represent a respective contact on the touch-sensitive surface without specifying the intensity of the respective contact. 
     In some embodiments, described herein, one or more operations are performed in response to detecting a gesture that includes a respective press input or in response to detecting the respective press input performed with a respective contact (or a plurality of contacts), where the respective press input is detected based at least in part on detecting an increase in intensity of the contact (or plurality of contacts) above a press-input intensity threshold. In some embodiments, the respective operation is performed in response to detecting the increase in intensity of the respective contact above the press-input intensity threshold (e.g., the respective operation is performed on a “down stroke” of the respective press input). In some embodiments, the press input includes an increase in intensity of the respective contact above the press-input intensity threshold and a subsequent decrease in intensity of the contact below the press-input intensity threshold, and the respective operation is performed in response to detecting the subsequent decrease in intensity of the respective contact below the press-input threshold (e.g., the respective operation is performed on an “up stroke” of the respective press input). 
     In some embodiments, the device employs intensity hysteresis to avoid accidental inputs sometimes termed “jitter,” where the device defines or selects a hysteresis intensity threshold with a predefined relationship to the press-input intensity threshold (e.g., the hysteresis intensity threshold is X intensity units lower than the press-input intensity threshold or the hysteresis intensity threshold is 75%, 90%, or some reasonable proportion of the press-input intensity threshold). Thus, in some embodiments, the press input includes an increase in intensity of the respective contact above the press-input intensity threshold and a subsequent decrease in intensity of the contact below the hysteresis intensity threshold that corresponds to the press-input intensity threshold, and the respective operation is performed in response to detecting the subsequent decrease in intensity of the respective contact below the hysteresis intensity threshold (e.g., the respective operation is performed on an “up stroke” of the respective press input). Similarly, in some embodiments, the press input is detected only when the device detects an increase in intensity of the contact from an intensity at or below the hysteresis intensity threshold to an intensity at or above the press-input intensity threshold and, optionally, a subsequent decrease in intensity of the contact to an intensity at or below the hysteresis intensity, and the respective operation is performed in response to detecting the press input (e.g., the increase in intensity of the contact or the decrease in intensity of the contact, depending on the circumstances). 
     For ease of explanation, the description of operations performed in response to a press input associated with a press-input intensity threshold or in response to a gesture including the press input are, optionally, triggered in response to detecting: an increase in intensity of a contact above the press-input intensity threshold, an increase in intensity of a contact from an intensity below the hysteresis intensity threshold to an intensity above the press-input intensity threshold, a decrease in intensity of the contact below the press-input intensity threshold, or a decrease in intensity of the contact below the hysteresis intensity threshold corresponding to the press-input intensity threshold. Additionally, in examples where an operation is described as being performed in response to detecting a decrease in intensity of a contact below the press-input intensity threshold, the operation is, optionally, performed in response to detecting a decrease in intensity of the contact below a hysteresis intensity threshold corresponding to, and lower than, the press-input intensity threshold. As described above, in some embodiments, the triggering of these responses also depends on time-based criteria being met (e.g., a delay time has elapsed between a first intensity threshold being met and a second intensity threshold being met). 
     User Interfaces and Associated Processes 
     Attention is now directed towards embodiments of user interfaces (“UI”) and associated processes that may be implemented on an electronic device, such as portable multifunction device  100  or device  300 , with a display, a touch-sensitive surface, and one or more sensors to detect intensities of contacts with the touch-sensitive surface. 
       FIGS. 5A-5TT  illustrate exemplary user interfaces for content navigation and manipulation in accordance with some embodiments. The user interfaces in these figures are used to illustrate the processes described below, including the processes in  FIGS. 6A-6B, 7A-7C, 8A-8C, 9A-9D, and 10A-10C . For convenience of explanation, some of the embodiments will be discussed with reference to operations performed on a device with a touch-sensitive display system  112 . In such embodiments, the focus selector is, optionally: a respective finger or stylus contact, a representative point corresponding to a finger or stylus contact (e.g., a centroid of a respective contact or a point associated with a respective contact), or a centroid of two or more contacts detected on the touch-sensitive display system  112 . However, analogous operations are, optionally, performed on a device with a display  450  and a separate touch-sensitive surface  451  in response to detecting the contacts on the touch-sensitive surface  451  while displaying the user interfaces shown in the figures on the display  450 , along with a focus selector. 
       FIGS. 5A-5TT  illustrate exemplary user interfaces for manipulating content items depending on the intensity (e.g., pressure) applied by a contact during a user gesture in accordance with some embodiments. The user interfaces in these figures are used to illustrate the processes described below, including the processes described below with reference to  FIGS. 6A-6B . 
       FIGS. 5A-5K  illustrate exemplary user interfaces that perform certain actions based on intensity characteristics of a user input (e.g., contact) in accordance with some embodiments. 
     For example,  FIGS. 5A-5C  illustrate an exemplary user interface of a device  100  that performs certain actions (e.g., scrolls through a content item) when a contact intensity of a user input does not exceed a predetermined threshold, in accordance with some embodiments. Alternatively,  FIGS. 5D-5H  illustrate an exemplary user interface that performs alternate actions (e.g., replaces a content item with another content item) when the contact intensity exceeds a predetermined threshold, in accordance with some embodiments. Lastly,  FIG. 5K  illustrates an exemplary user interface that displays a preview of a selectable affordance when certain criteria of the user input are met. 
     Turning now to  FIG. 5A ,  FIG. 5A  illustrates a user interface of device  100  before device  100  performs certain actions (e.g., scrolls through a content item) based on characteristics of the user input. The device  100  displays a content item (e.g., content item  502 ) on a display. In some embodiments, content item  502  is an email message in an email application including an email content section  502   a , an email title section  502   b , and an email header section  502   c . While the examples shown in  FIGS. 5A-5K  illustrate content item  502  as an email message, in some embodiments, content item  502  may be other content items, including web pages, books, images, text, among other types. In some embodiments, content item  502  is associated with a sequence of content items, such as plurality of electronic messages in an electronic messaging application, a plurality of web browser windows (or tabbed windows) in a web browser, a plurality of applications, a plurality of digital images in a set of images (e.g., a single album or collection in a photo or camera application), or a plurality of sets of digital images (e.g., a plurality of albums or collections of photos in a photo or camera application). In some embodiments, the sequence of content items corresponds to a plurality of content sections, such as a plurality of conversations in a messaging or email application, a plurality of weeks (or months or years) in a calendar application, a plurality of chapters in a book, a plurality of scenes in a video, or a plurality of events in a digital image library. 
     In addition to the email message, the device  100  also displays other components of the email application, including an email tool bar  503 . The email tool bar  503  includes selectable affordances (e.g., a left-arrow  504 , an up-arrow  506 , and a down-arrow  508 ). A section label (e.g., “inbox”) is associated with the left-arrow. In some embodiments, when a user selects a selectable affordance (e.g., the left arrow  504 ), as shown via user input  511  in  FIG. 5I , the device  100  displays a plurality of content items (e.g., email messages  502 ,  518 ,  520   a ,  520   b , and  520   c , associated with a user&#39;s inbox) on the display (e.g., touch screen  112 ), as shown in  FIG. 5J . When a user selects the up-arrow  506 , the email application displays a content item preceding the currently-displayed content item  502  (e.g., a preceding email message in the user&#39;s inbox). When a user selects the down-arrow  508 , the device  100  displays a content item following the currently-displayed content item  502  (e.g., a successive email message in the user&#39;s inbox). 
       FIG. 5B  illustrates a user interface, subsequent to  FIG. 5A , after the device  100  detects a user input  510  (e.g., a contact) on the content item  502  and before the device  100  performs certain actions (e.g., scrolls through a content item) based on characteristics of the user input, in accordance with some embodiments. In some embodiments, the device  100  detects movement (e.g., press, flick, swipe) and/or intensity (e.g., contact, light, deep) of user input  510 . For illustrative purposes, and not part of the device  100 , user inputs are represented as a circle on device  100 , where the density of the dots speckled within the circle represents the intensity exerted by the user. In  FIG. 5B , the dots speckled within the circle are low density, meaning the user is exerting low pressure. Also, for illustrative purposes, and not part of the device  100 , some of  FIGS. 5B-5K  include an intensity diagram  501  indicating the intensity of a user input determined by the device  100 . The intensity diagram  501  includes a plurality of exemplary thresholds (e.g., contact detection threshold IT 0 , “hint” threshold IT H , light press threshold IT L , and deep press threshold IT D ). In  FIG. 5B , because the user is exerting low intensity that falls between the contact detection threshold IT 0  and “hint” threshold IT H , the intensity diagram includes shading that rises to a level between these two thresholds. In subsequent Figures, the amount of shading in the intensity diagram indicates the intensity exerted by a user at a user input. Lastly, for illustrative purposes, and not part of the device  100 , user input movement (e.g., movement of the contact of the user input on the touch-sensitive surface) is represented as a vector (e.g., vector  512 ,  FIG. 5B ), where the direction of the vector represents the direction of the user input movement and the magnitude of the vector represents the amount of movement of the user input (e.g., user input  510 ,  FIG. 5B ). 
     The device  100  is configured to navigate a content item or replace a content item with another content item based on the received user input. In response to detecting a user input, the device  100  determines whether the user input meets item-switching criteria. The item-switching criteria includes a criterion that is met when a characteristic intensity of a contact in the user input is above a first intensity threshold (e.g., “hint” threshold IT H , light press threshold IT L , or deep press threshold IT D ). In some embodiments, if the characteristic intensity of the user input is below the first intensity threshold, the device  100  navigates or scrolls through the content of the content item  502  in accordance with the movement of the user input. 
     For example, in  FIG. 5B , the characteristic intensity of the user input  510 , as shown in the intensity diagram  501 , is below a first intensity threshold associated with item-switching criteria (e.g., light press threshold IT L ). In some embodiments, the device  100  detects movement  512  of the user input in a respective direction on touch screen  112  and navigates or scrolls through the content of the content item  502  in accordance with the movement of the user input  510 . In some embodiments, as shown in  FIG. 5B , the user input  510  is a swipe/drag gesture that is made with a contact. In some embodiments, the swipe/drag gesture includes movement of the contact from a first position (e.g., position  510 - 1 ) on the touch-sensitive surface to a second position (e.g., position  510 - 2 ) on the touch-sensitive surface. In some embodiments, the swipe/drag gesture is a vertical swipe gesture (as shown in  FIG. 5B ). In some embodiments, the swipe gesture is a horizontal swipe gesture. 
     In some embodiments, when the device  100  detects the user input  510  and the characteristic intensity of the user input  510  is below the first intensity threshold (e.g., light press threshold IT L ), the device  100  displays a scroll bar  514  indicating the location of the portion of content displayed to the user relative to the entire content item  502 . As the device  100  navigates through the content of the content item  502  and displays different content portions of the content item, the device  100  moves the scroll bar  514  to different positions relative to the content portion of the content item displayed to the user. 
     For example,  FIG. 5C  illustrates a user interface, subsequent to  FIG. 5B , of a device  100  after the device  100  performs certain actions (e.g., scrolls through a content item) based on characteristics of the user input, in accordance with some embodiments. As shown, the user input  510  moved to second position  510 - 2  from first position  510 - 1 . In response to the movement of the user input  510 , the device  100  navigates through the content of the content item  502  and displays a second content portion of the content item  502 , where the second content portion is different from the first content portion. In addition, the device  100  moves the scroll bar  514  to a second position that is different from the position of the scroll bar  514  in  FIG. 5B . 
     In some embodiments, the device  100  scrolls the content in a direction on the display in an opposite direction relative to the movement of the user input  510 . In some embodiments, the device  100  scrolls the content in a direction on the display in a same direction relative to the movement of the user input  510 . In some embodiments, navigating through the content of the first content item includes directly manipulating the displayed content of the first content item in accordance with the movement of the contact. For example, the movement (e.g., speed, direction, and/or distance) of the content, when scrolled, tracks the movement of the contact. 
     In some embodiments, the device  100  maintains display of a first portion of the first content item in a first user interface region on the display; and navigates (e.g., scrolls) through a second portion of the first content item in a second user interface region on the display. For example, as shown in  FIGS. 5B-5C , when scrolling the content within a content item  502 , a portion of the content item (e.g., email tool bar  503 ) is fixed relative to the content (e.g., the body  502   a  of content item  502  and the email title section  502   b  of content item  502 ). 
       FIG. 5D-5I  illustrate certain actions (e.g., replacing content item  502  with another content item), performed by the device  100  when the user input meets item-switching criteria, in accordance with some embodiments. In some embodiments, if the characteristic intensity of the user input is above a first intensity threshold (e.g., “hint” threshold IT H , light press threshold IT L , or deep press threshold IT D ), the device  100  replaces display of the content item  502  with display of a second content item  518  (e.g., a different content item distinct from the content item  502 ). In some embodiments, the device  100  replaces display of the content item  502  with display of second content item  518  in accordance with other criteria being met as well. For example, as shown in  FIG. 5E , the device initiates replacing display of the first content item with a second content item when a user input is detected with an increase in contact intensity in conjunction with at least a minimum amount of movement of the contact. 
       FIG. 5D  is analogous to  FIG. 5A .  FIGS. 5E-5I  illustrate operations performed by device  100  in response to detecting a user input  513 . 
       FIG. 5E  shows user input  513 , which is analogous to user input  510  ( FIGS. 5B-5C ) except that user input  513  has an intensity that exceeds a “hint” threshold IT H . In response, the device  100  reduces (e.g., decreases) the size of content item  502  (e.g., zooms-out on content item  502  in a z-direction). In some embodiments, the zooming out of content item  502  provides a hint to the user that user input  513  will result in different functionality by virtue of being a deeper press (e.g., as compared to user input  510 ,  FIGS. 5B-5C ). In some embodiments, the size reduction of content item  502  is directly controllable by the user, e.g., via the intensity of the user input  513 . So, for example, as the user increases the contact intensity of a user input  513  toward the light press intensity threshold IT L  (as shown in intensity diagram  501 ), the content item  502  zooms-out (e.g., reduces in size). If the user subsequently slightly reduces the intensity of the contact of the user input  513 , the content item  502  zooms back in. In some embodiments, a plurality of intensity levels within the vicinity of the light press intensity threshold IT L  (e.g., a plurality of intensity levels between IT H  and IT L ) map to a plurality of corresponding zoom levels (e.g., sizes) of content item  502 . Thus, the user feels as though she is pushing the first content item back in the z-direction by pushing harder on the contact. In some embodiments, as a result of reducing the size of the first content item, a region  516  beyond an edge of the content item  502  is displayed (e.g., a background area that is a different color or pattern than a color or pattern of the background of the content item  502 ), illustrating to the user that the content item  502  has been pushed back in the z-direction. 
     In some embodiments, the device  100  transitions to replacing display of the first content item with a second content item in response to a user input (e.g., replacing content item  502  with another content item) when the characteristic intensity exceeds the light press intensity threshold IT L  (e.g., an intensity threshold that is greater than the “hint” threshold IT H ). In some embodiments, the user can zoom-in to or zoom-out from the content item  502  if the characteristic intensity exceeds the “hint” threshold IT H  and does not exceed the light press threshold IT L . However, in some embodiments, the device  100  does not transition to another content item until the characteristic intensity exceeds the light press threshold IT L . Thus, in some embodiments, there is a range of intensities for which device  100  provides a hint that content item replacement will be performed based on the intensity of the contact (as well as other optional criteria), but does not yet provide that functionality. 
       FIG. 5F  illustrates a user interface, subsequent to  FIG. 5E . In  FIG. 5F , device  100  is replacing content item  502  with second content item  518 , in accordance with some embodiments (e.g., device  100  is displaying a transition between content item  502  and second content item  518 ). In some embodiments, device  100  determines whether to replace content item  502  with second content item  518  based at least in part on the intensity of the user input  513 .  FIG. 5F  illustrates movement of the user input  513  (e.g., represented by vector  515 ). As shown, movement of the user input  513  begins at a first position (e.g., position  513 - 1 ) on the touch-sensitive surface and ends at a second position (e.g., position  513 - 2 ) on the touch-sensitive surface. 
     The device  100  transitions from the content item  502  to the second content item  518  when certain item-switching criteria are met. In some embodiments, the device  100  transitions from the content item  502  to second content item  518  when the intensity of the user input  513  exceeds a predetermined threshold (e.g., a light press threshold IT L ). In some embodiments, the device  100  transitions from the content item  502  to second content item  518  when the movement of user input  513  also exceeds a predetermined movement threshold (e.g., when the device detects a predetermined amount or distance of movement of the contact that exceeds a predetermined movement threshold). That is, in some embodiments, there is a predetermined magnitude of intensity and movement of user input  513  that is required to be detected by device  100  in order to cause the device  100  to replace display of content item  502  with display of second content item  518  rather than, e.g., scroll content item  502 . 
       FIG. 5G  illustrates the user interface subsequent to  FIG. 5F . In  FIG. 5G , device  100  has progressed further in replacing content item  502  with second content item  518  (as compared to  FIG. 5F ). As shown, the user input  513  moved to second position  513 - 2  from first position  513 - 1 . In response to the movement of the user input  513 , the device  100  replaces display of the content item  502  with the display of the second content item  518 . 
     In certain situations, device  100  either replaces display of the content item  502  or scrolls through content item  502  based on other characteristics (e.g., timing of intensity or movement) of a user input. For example, in some embodiments, if an initial intensity of the contact does not exceed an intensity threshold (e.g., “hint” threshold IT H  in  FIGS. 5B-5C ), device  100  scrolls the content item  502  in response to the beginning of the user input (e.g., an initial portion of a swipe gesture). If later, during the user input, the contact of the user input exceeds the intensity threshold, device  100  transitions to displaying a second content item (as in  FIGS. 5E-5H ). In some embodiments, the item-switching criteria are met when the initial intensity of the contact exceeds the first intensity threshold. In some embodiments, the item-switching criteria are met when the initial intensity of the contact exceeds the first intensity threshold while the contact is moving (e.g., moving above a predetermined velocity threshold). In some embodiments, the item-switching criteria are not met if the contact is stationary or is moving below a predetermined velocity threshold, even if the characteristic intensity of the contact exceeds the first intensity threshold. 
     In some embodiments, the device  100  automatically completes replacing content item  502  with second content item  518  when the user has dragged the second content item  518  sufficiently onto touch screen  112 . For example, as shown in  FIG. 5G , the user input  513  has moved the midpoint  520  between content item  502  and second content item  518  past a predetermined positional threshold  517  (e.g., half-way, or a third of the way up touch screen  112 ). As shown in  FIG. 5H , the user terminates user input  513  (e.g., lifts off of touch screen  112 ), but the device  100  continues to animate a transition to the second content item  518  ( FIGS. 5H-5I ). In some embodiments, the predetermined positional threshold may be positioned at alternative locations on touch screen  112 . 
     Thus, as shown in  FIG. 5D-5I , in some embodiments, replacing display of the content item  502  with the second content item  518  includes displaying a transition between the content item  502  and the second content item  518  (e.g., in which content item  502  zooms-out, slides upward off of touch screen  112  while second content  518  slides upward onto touch screen  112 , and second content item  518  zooms-in to complete the animated transition). The transition includes concurrently displaying at least a portion of the content item  502  and at least a portion of the second content item  518  (as shown in  FIGS. 5E-5G , for example). In some embodiments, the transition is dynamically controlled by the user input  513  (e.g., the user can directly manipulate the progress of the transition via user input  513 ).  FIG. 5I  also illustrates user input  511  corresponding to selection of affordance  504 . 
       FIG. 5J  illustrates the result of user input  511 , namely that the device  100  navigates back to a user interface showing a list view of the user&#39;s emails (including content item  502 , content item  518 , and additional emails  520   a  through  520   c ).  FIG. 5J  illustrates that, in some embodiments, the second content item  518  is sequentially adjacent to the content item  502  (e.g. in the sequence of content items, as shown in  FIG. 5J ) and is selected based on the respective direction of the movement of the user input  513 . That is, in some embodiments, a deep swipe transitions to the next email or previous email depending on the swipe direction, while a normal swipe (e.g., a swipe with a characteristic intensity below a predefined threshold) scrolls the currently displayed email. 
       FIG. 5K  illustrates an exemplary user interface that displays a preview of a selectable affordance when certain intensity criteria of the user input are met. 
     In some embodiment, device  100  detects a user input  519  that is stationary (e.g., includes movement of a contact that is less than a predefined threshold) and over a selectable affordance but is otherwise analogous to user input  513  (e.g., the contact intensity of user input  519  is above the first intensity threshold associated with item-switching criteria, such as light press threshold IT L ). In response to user input  519 , the device  100  displays a preview area  521  of content that corresponds to the selectable affordance overlaid on the content item  502 . Thus, in some embodiments, a press input over a selectable affordance within content item  502 , where the press input has an intensity above IT L , triggers different functionality than a swipe/drag over content item  502 , where the swipe/drag has an intensity above IT L . 
       FIGS. 5L-5U  illustrate exemplary user interfaces for reordering list items in accordance with some embodiments. The user interfaces in these figures are used to illustrate the processes described below, including the processes described below with reference to  FIGS. 7A-7C . 
       FIG. 5L  illustrates a portion of a list of items, in accordance with some embodiments. A list of items  532  includes items  534 ,  536 ,  538 ,  540 ,  542 ,  544 ,  546 , and  548 , as indicated at  FIGS. 5L-5U . In  FIG. 5L , a portion of the list of items including items  534 ,  536 ,  538 ,  540 ,  542 , and  544  is presented on touch screen  112 . 
       FIGS. 5M-5N  illustrate scrolling of list of items  532  when movement is detected while a characteristic intensity of the contact remains below a first intensity threshold. 
     In  FIG. 5M , a contact is received at touch screen  112  at a location indicated by focus selector  550 . The contact moves across touch screen  112  along a path indicated by arrow  552 . A portion of list  532 , including items  534 ,  536 ,  538 ,  540 ,  542 , and  544 , is presented on touch screen  112 . As the movement of the contact occurs, list  532  is scrolled in the direction of movement of the contact. A currently viewed position within list  532  (e.g., relative to the overall length of list  532 ) is indicated by scroll position indicator  554 . In  FIG. 5M , the characteristic intensity of the contact is between a contact detecting intensity threshold IT 0  and a hint intensity threshold IT H , as indicated by intensity meter  530 . 
     In  FIG. 5N , list  532  has been scrolled in accordance with the movement of the contact from an initial position as indicated by focus selector  550   a  (e.g., focus selector  550  at a first point in time) to a subsequent position as indicated by focus selector  550   b  (e.g., focus selector  550  at a second point in time that is later than the first point in time) along the path indicated by arrow  552 . As a result of the changed currently viewed position within list  532  due to movement of the contact, a second portion of list  532 , including items  546  and  548 , is presented. Items  542  and  544  of list  532  are no longer visible. Scroll position indicator  554  is shown at a higher position in the user interface of  5 N than the position of scroll position indicator  554  in the user interface of  5 M. 
       FIG. 5O  illustrates a changed appearance of an item, in accordance with some embodiments. The contact is at the location of item  534 , as indicated by focus selector  550 . The contact moves across touch screen  112  along a path indicated by arrow  556 . The characteristic intensity of the contact is above a hint intensity threshold IT H , as indicated by intensity meter  530 . The appearance of item  534  is changed (e.g., a rectangular outline is shown around item  534  to highlight the item). In response to the increase of the characteristic intensity of the contact above intensity threshold IT H  followed by the movement of the contact, the appearance of item  534  has changed (e.g., to indicate to the user that item  534  is detachable from list  532  and/or on the verge of detachment). 
       FIGS. 5P-5U  illustrate moving an item relative to other items, in accordance with some embodiments. 
     In  FIG. 5P , the contact moves across touch screen  112  from the location indicated by focus selector  550  along a path indicated by arrow  556 . The characteristic intensity of the contact is above a hint intensity threshold IT L , as indicated by intensity meter  530 . In response to the increase of the characteristic intensity of the contact above intensity threshold IT L  followed by the movement of the contact along the path indicated by arrow  556 , item  534  has moved (from the position of item  534  as shown in  FIGS. 5N-5O ) relative to the other items  536 ,  538 ,  540 ,  546 , and  548 . 
       FIGS. 5P-5R  illustrate movement of item  534  that lags movement of the contact as the focus selector  550  moves across touch screen  112  along the path indicated by arrow  556 . 
     In  FIG. 5P , item  534  has detached from list  532 . The detachment of item  534  from list  532  is indicated by, e.g., changes in the appearance of item  534  (such as a reduced size of item  534  relative to the other items in list  532 ) and changes in the position of item  532  (such as a vertical and/or z-axis shifting of item  534  relative to the previous location of item  534  shown in  FIGS. 5L-5O ). A first item slot  558  is partially revealed as a result of the movement of item  534 . 
     In  FIGS. 5P-5Q , as the contact moves along a first portion of the path indicated by arrow  556  (as indicated by the movement of focus selector  550  from the location shown in  FIG. 5P  to the location of focus selector  550  shown in  FIG. 5Q ), item  534  remains static (or moves more slowly than focus selector  550 ). In  FIG. 5Q , focus selector  550  extends below the lower edge of item  534 . In  FIG. 5R , as focus selector  550  has continued the movement along a second portion of the path indicated by arrow  556 , item  534  has accelerated (e.g., to “catch up” with focus selector  550 ) and focus selector  550  is again shown in the center of item  534 . The characteristic intensity of the contact is above a light press intensity threshold IT L , as indicated by intensity meter  530 . In response to the increase of the characteristic intensity of the contact above intensity threshold IT L  followed by the movement of the contact along the path indicated by arrow  556 , item  534  has moved (from the position of item  534  as shown in  FIGS. 5N-5O ) relative to the other items  536 ,  538 ,  540 ,  546 , and  548 . 
     In  FIG. 5S , as focus selector  550  has moved along the path indicated by arrow  556  from a location indicated by focus selector  550   c  (focus selector  550   c  at a point in time) to a location indicated by focus selector  550   d  (focus selector  550  at a point in time later than the time of  550   c ), item  534  has continued to move relative to item  536  such that item  534  has moved “over” item  536 . Item  536  has moved into first item slot  558  (that was previously occupied by item  534  prior to the detachment of item  534  from list  532 ). A second item slot  560  is revealed. As a result of the movement of item  536  into first item slot  558  and the revelation of second item slot  560 , tactile feedback (as indicated at  562 ) is generated. 
     In FIG.  5 T 1 , item  534  is shown inserted into second item slot  560 . Item  534  is inserted into second item slot  560 , e.g., as a result of lift off of the contact from touch screen  112  while second item slot  560  is revealed (e.g., as shown in  FIG. 5S ). 
     FIGS.  5 T 2 - 5 U illustrate scrolling of list  532  that occurs in response to item  534  moving within a threshold distance of the end of the displayed portion of list  532 . 
     In FIG.  5 T 2 , the contact moves (e.g., continuing from the movement of the contact as indicated in  FIG. 5S ) from the location indicated by focus selector  550  along a path indicated by arrow  564  toward a lower end  566  of the displayed portion of list  532 . 
     In  FIG. 5U , as a result of movement of the contact to a location that is within a threshold distance of the lower end  566  of the displayed portion of the list  532 , the list  532  is scrolled toward upper end  568  of the displayed portion of the list  532 , revealing items  542  and  544  that were not visible in FIG.  5 T 2 . Scroll position indicator  554  is shown at a lower position in the user interface of  5 U than the position of scroll position indicator  554  in the user interface of  5 T 2 . As a result of the movement of item  544  into a new item slot and the revelation of previous item slot  570  for item  544  (which previously occupied previous item slot  570 ), tactile feedback (as indicated at  562 ) is generated. 
       FIGS. 5V-5CC  illustrate exemplary user interfaces for navigating structured content in accordance with some embodiments. The user interfaces in these figures are used to illustrate the processes described below, including the processes described below with reference to  FIGS. 8A-8C . 
       FIG. 5V  illustrates a first portion (e.g., Chapter 3) of structured content  572  (e.g., the book  The Jungle Book  by Rudyard Kipling) displayed by touch screen  112 . 
       FIG. 5W-5X  illustrate translation of structured content  572  in accordance with movement of a contact, in accordance with some embodiments. 
     In  FIG. 5W , a contact with touch screen  112  is detected at a location indicated by focus selector  574 . The contact moves across touch screen  112  along a path indicated by arrow  578 . A characteristic intensity of the contact is between a contact detecting intensity threshold IT 0  and a hint intensity threshold IT H , as indicated by intensity meter  530 . A currently viewed position within structured content  572  (e.g., relative to the overall length of structured content  572 ) is indicated by scroll position indicator  576 . 
     In  FIG. 5X , structured content  572  has been scrolled in accordance with the movement of the contact from an initial position as indicated by focus selector  574   a  (e.g., focus selector  574  at a first point in time) to a subsequent position as indicated by focus selector  574   b  (e.g., focus selector  574  at a second point in time that is later than the first point in time) along the path indicated by arrow  578 . As a result of the changed currently viewed position within structured content  572  due to movement of the contact, structured content  572  is translated. Scroll position indicator  576  is shown at a lower position in the user interface of  5 X than the position of scroll position indicator  576  in the user interface of  5 W (e.g., to indicate the advanced position of the currently viewed position within structured content  572  as a result of the translation). 
       FIGS. 5Y-5Z  illustrate applying a visual effect to structured content  572  and presenting a scroll bar including a scroll position indicator  576 , in accordance with some embodiments. 
     In  FIG. 5Y , a contact is received on touch screen  112  at a location indicated by focus selector  574 . The characteristic intensity of the contact is below intensity threshold IT H , as indicated by intensity meter  530 . Scroll position indicator  576  is shown (e.g., in response to the increase in the characteristic intensity of the contact to above IT 0 ) to indicate a position of the displayed portion of structured content  572  within structured content  572 . 
     In  FIG. 5Z , the intensity of the contact has increased from below hint intensity threshold level IT H , as indicated by intensity meter  530  of  FIG. 5Y , to above intensity threshold IT H , as indicated by intensity meter  530  of  FIG. 5Z . The contact moves across touch screen  112  along a path indicated by arrow  580 . In response to the increase in the characteristic intensity of the contact (e.g., the increase above intensity level IT H ) and the movement of the contact, a visual effect is applied to the displayed section of structured content  572 . The applied visual effect includes shrinking the displayed portion of structured content  572  and pushing the displayed portion of structured content  572  to a lower z-level on touch screen display  112 . 
     In response to the increase in the characteristic intensity of the contact (e.g., the increase above intensity level IT H ), as indicated in  FIG. 5Z , section indicators  582 ,  584 ,  586 , and  588  are presented along with scroll position indicator  576 . Section indicator  586  (which is the closest of the section indicators to scroll position indicator  576 ), corresponds to the displayed portion (“Chapter 3”) of structured content  572 . Section indicators  582  and  584  correspond to portions (e.g., Chapters 1 and 2, respectively) of structured content  573  prior to the displayed portion. Section indicator  588  corresponds to a portion (e.g., Chapter 4) of structured content  573  following the displayed portion. 
       FIGS. 5AA-5BB  illustrate translating structured content  572  to show a start of a next section, in accordance with some embodiments. 
     In  FIG. 5AA , a characteristic intensity of the contact has increased from below hint intensity threshold level IT L , as indicated by intensity meter  530  of  FIG. 5Z , to above light press intensity threshold IT L , as indicated by intensity meter  530  of  FIG. 5AA . In response to the increase in the characteristic intensity of the contact and the movement of the contact along the path indicated by arrow  580 , and because the characteristic intensity of the contact increased above light press intensity threshold IT L , structured content  572  is translated to display a start of an adjacent section. For example, as described with regard to  FIG. 5BB , a next section (“Chapter 4”) is displayed, e.g., in accordance with the direction of the movement of the contact indicated by arrow  580 . Section indicators  582 ,  584 ,  586 , and  588  are spread from initial positions, as shown in  FIG. 5Z , to adjusted positions, as shown in  FIG. 5AA . In  FIG. 5AA , that distances between adjacent section indicators are greater than the distances between the initial positions of section indicators as shown in  FIG. 5Z . 
     In  FIG. 5BB , the contact has moved from a position indicated by focus selector  574   c  (focus selector  574  at a position in time) to a position indicated by focus selector  574   d  (focus selector  574  at a position in time that is later than the time of  574   c ). A next section (“Chapter 4”) of structured content  572  is displayed. Scroll position indicator  576  has moved from a position adjacent to section indicator  586 , as indicated in  FIG. 5AA , to a position adjacent to section indicator  588  (e.g., the scroll position indicator has “hopped” over section indicator  588 ), as indicated in  FIG. 5BB , to indicate the occurrence of the translation to the adjacent section. 
       FIG. 5CC  illustrates a displayed next section of structured content  572  after liftoff of the contact has occurred, in accordance with some embodiments. In response to the liftoff of the contact, scroll position indicator  576  and section indicators  582 ,  584 ,  586 , and  588  are no longer displayed. Structured content  572  is returned to its initial size (e.g., the adjacent section is displayed at the same size of the section of structured content  572  displayed in  FIG. 5Y ). 
       FIGS. 5DD-5TT  illustrate exemplary user interfaces for moving content on a display in accordance with some embodiments. The user interfaces in these figures are used to illustrate the processes described below, including the processes in  FIGS. 9A-9D and 10A-10C . 
       FIGS. 5DD-5GG  illustrate content scrolling ( FIGS. 5DD and 5EE ) and movement of content occurring in response to lift-off of a contact ( FIGS. 5FF and 5GG ) when a detected characteristic intensity of a contact has a first intensity prior to lift-off, in accordance with some embodiments. 
     In  FIG. 5DD , a contact is detected at touch on touch screen  112  at a location indicated by focus selector  594 . The contact moves along a path indicated by arrow  598 . A first portion of content  592  (the poem “The Raven” by Edgar Allan Poe) is presented on touch screen display  112 . As the movement of the contact occurs, content  592  is scrolled (e.g., in the direction of movement of the contact). A currently viewed position within content  592  (e.g., relative to the overall length of content  592 ) is indicated by scroll position indicator  596 . In  FIG. 5DD , the intensity of the contact is between a contact-detection intensity threshold IT 0  and a hint intensity threshold IT H , as indicated by intensity meter  530 . 
     In  FIG. 5EE , content  592  has been scrolled in accordance with the movement of the contact from an initial position as indicated by focus selector  594   a  (e.g., focus selector  594  at a first point in time) to a subsequent position as indicated by focus selector  594   b  (e.g., focus selector  594  at a second point in time that is later than the first point in time) along the path indicated by arrow  598 . In accordance with the changed currently viewed position within content  592 , scroll position indicator  596  is shown at a lower position in  5 EE than the position of scroll position indicator  596  in  5 DD. 
     In  FIG. 5FF , following movement of the contact as described with regard to  FIGS. 5DD-5EE , lift-off of the contact from touch screen  112  has occurred. In response to the lift-off of the contact following the movement of the contact, the content  592  moves at a velocity (also referred to herein as “speed”) v 1 , as indicated by dotted arrow  5100 . 
     In  FIG. 5GG , the movement of content  592  continues at a reduced velocity v 2 , as indicated by dotted arrow  5100 . The velocity of the movement is reduced from velocity v 1 , as indicated in  FIG. 5FF , to velocity v 2 , as indicated in  5 GG, (e.g., to indicate a friction effect). For example, the movement of the content slows due to virtual friction between content  592  and the virtual surface over which content  592  is moving. 
       FIGS. 5HH-5KK  illustrate content scrolling ( FIGS. 5HH and 5II ) and movement of content occurring in response to lift-off of a contact ( FIGS. 5JJ and 5KK ) when a detected characteristic intensity of a contact has a second intensity prior to lift-off, in accordance with some embodiments. 
     In  FIG. 5HH , a contact is detected at touch on touch screen  112  at a location indicated by focus selector  594 . The contact moves along a path indicated by arrow  5102 . A first portion of content  592  is presented on touch screen display  112 . As the movement of the contact occurs, content  592  is scrolled (e.g., in the direction of movement of the contact). A currently viewed position within content  592  (e.g., relative to the overall length of content  592 ) is indicated by scroll position indicator  596 . In  FIG. 5HH , the intensity of the contact has increased above a light press intensity threshold IT L , as indicated by intensity meter  530 . Scroll enhancement indicator  5104  is shown (e.g., to indicate an extent to which the characteristic intensity of the contact is affecting content scrolling and/or post-lift-off content movement behavior). For example, the length of scroll enhancement indicator  5104  provides a visual indication of a simulated inertia of content  592  that occurs on lift-off (e.g., the resistance to slowing down after lift-off from the velocity with which content  592  is moving in response to the movement of the contact prior to lift-off). In some embodiments, a simulated inertia is set based on a characteristic intensity of the contact. 
     In  FIG. 511 , content  592  has been scrolled in accordance with the movement of the contact from an initial position as indicated by focus selector  594   c  (e.g., focus selector  594  at a first point in time) to a subsequent position as indicated by focus selector  594   d  (e.g., focus selector  594  at a second point in time that is later than the first point in time) along the path indicated by arrow  5102 . In accordance with the changed currently viewed position within content  592 , scroll position indicator  596  is shown at a lower position in  511  than the position of scroll position indicator  596  in  5 HH. 
     In  FIG. 5JJ , following movement of the contact as described with regard to  FIGS. 5HH-5II , lift-off of the contact from touch screen  112  has occurred. In response to the lift-off of the contact following the movement of the contact, the content  592  moves at a velocity v 3 , as indicated by dotted arrow  5106 . Compared with the velocity of movement of content  592  that occurred as indicated in  FIGS. 5FF-5GG , content  592  moves with a greater velocity in  FIGS. 5JJ-5KK  (e.g., v 3  is greater than v 1 ) in accordance with the higher characteristic intensity of the contact with touch screen  112  prior to lift-off as indicated in  FIGS. 5HH-5II . 
     In  FIG. 5KK , the movement of content  592  continues at a reduced velocity v 4 , as indicated by dotted arrow  5106 . The velocity of the movement is reduced from velocity v 3 , as indicated in  FIG. 5JJ , to velocity v 4 , as indicated in  5 KK (e.g., to indicate a friction effect). Compared with the movement of content  592  that occurred in response to liftoff as indicated in  FIGS. 5FF-5GG , content  592  moves by a greater distance in FIGS.  5 JJ- 5 KK in accordance with the higher characteristic intensity of the contact with touch screen  112  prior to lift-off as indicated in  FIGS. 5HH-5II . 
       FIGS. 5LL-5OO  illustrate content scrolling ( FIGS. 5LL and 5MM ) and movement of content occurring in response to lift-off of a contact ( FIGS. 5NN and 5OO ) when a detected characteristic intensity of a contact has a third intensity prior to lift-off, in accordance with some embodiments. 
     In  FIG. 5LL , a contact is detected on touch screen  112  at a location indicated by focus selector  594 . The contact moves along a path indicated by arrow  5108 . A first portion of content  592  is presented on touch screen display  112 . As the movement of the contact occurs, content  592  is scrolled (e.g., in the direction of movement of the contact). A currently viewed position within content  592  (e.g., relative to the overall length of content  592 ) is indicated by scroll position indicator  596 . In  FIG. 5LL , the intensity of the contact has increased further above a light press intensity threshold IT L , to just below deep press intensity threshold IT D  (e.g., the characteristic intensity of the contact indicated in  FIG. 5LL  exceeds the characteristic intensity of the contact as indicated in  FIG. 5HH ), as indicated by intensity meter  530 . Scroll enhancement indicator  5104  of  FIG. 5LL  is longer than scroll enhancement indicator  5104  of  FIG. 5HH  (e.g., visually indicating the speed of the content&#39;s motion). 
     In  FIG. 5MM , content  592  has been scrolled in accordance with the movement of the contact from an initial position as indicated by focus selector  594   e  (e.g., focus selector  594  at a first point in time) to a subsequent position as indicated by focus selector  594   f  (e.g., focus selector  594  at a second point in time that is later than the first point in time) along the path indicated by arrow  5108 . In accordance with the changed currently viewed position within content  592 , scroll position indicator  596  is shown at a lower position in  5 MM than the position of scroll position indicator  596  in  5 LL. 
     In  FIG. 5NN , following movement of the contact as described with regard to  FIGS. 5LL-5MM , lift-off of the contact from touch screen  112  has occurred. In response to the lift-off of the contact following the movement of the contact, the content  592  moves at a velocity v 5 , as indicated by dotted arrow  5110 . Compared with the velocity of movement of content  592  that occurred as indicated in  FIGS. 5JJ-5KK , content  592  moves with a greater velocity in  FIGS. 5NN-5OO  (e.g., v 5  is greater than v 3 ) in accordance with the higher characteristic intensity of the contact with touch screen  112  prior to lift-off as indicated in  FIGS. 5LL-5MM . 
     In  FIG. 5OO , the movement of content  592  continues at a reduced velocity v 6 , as indicated by dotted arrow  5110 . The velocity of the movement is reduced from velocity v 5 , as indicated in  FIG. 5NN , to velocity v 6 , as indicated in  500  (e.g., to indicate a friction effect). Compared with the movement of content  592  that occurred in response to liftoff as indicated in  FIGS. 5JJ-5KK , content  592  moves by a greater distance in  FIGS. 5NN-5OO  in accordance with the higher characteristic intensity of the contact with touch screen  112  prior to lift-off as indicated in  FIGS. 5LL-5MM . Scroll enhancement indicator  5104  of  FIG. 5OO  is shorter than scroll enhancement indicator  5104  of  FIG. 5NN  (e.g., visually indicating the reduced speed of the content&#39;s motion). 
       FIGS. 5PP-5RR  illustrate scrolling through content  592  to a predefined portion of the content in response to lift-off of a contact when the contact had a characteristic intensity above an intensity threshold prior to the lift-off of the contact, in accordance with some embodiments. 
     In  FIG. 5PP , a contact is detected at touch on touch screen  112  at a location indicated by focus selector  594 . The contact moves along a path indicated by arrow  5112 . A first portion of content  592  is presented on touch screen display  112 . As the movement of the contact occurs, content  592  is scrolled (e.g., in the direction of movement of the contact). A currently viewed position within content  592  (e.g., relative to the overall length of content  592 ) is indicated by scroll position indicator  596 . In  FIG. 5PP , the intensity of the contact has increased above a deep press intensity threshold IT D , as indicated by intensity meter  530 . 
     In  FIG. 5QQ , content  592  has been scrolled in accordance with the movement of the contact from an initial position as indicated by focus selector  594   g  (e.g., focus selector  594  at a first point in time) to a subsequent position as indicated by focus selector  594   h  (e.g., focus selector  594  at a second point in time that is later than the first point in time) along the path indicated by arrow  5112 . In accordance with the changed currently viewed position within content  592 , scroll position indicator  596  is shown at a lower position in  5 QQ than the position of scroll position indicator  596  in  5 PP. 
     In  FIG. 5RR , following movement of the contact as described with regard to  FIGS. 5PP-5QQ , lift-off of the contact from touch screen  112  has occurred. In response to the lift-off of the contact following the movement of the contact, in accordance with a determination that the contact had a characteristic intensity above an intensity threshold (e.g., deep press intensity threshold IT D ) content  592  is scrolled to a predefined portion (e.g., the end of content  592  as indicated by scroll position indicator  596  in  5 RR). 
       FIG. 5SS  illustrates an intensity filter, in accordance with some embodiments. Solid line  5114  indicates a detected intensity of a contact. Dotted line  5116  indicates a shifted intensity profile that indicates filtered intensity values based on the detected intensity values indicated by detected intensity  5114 . The intensity filter shifts an intensity profile of a contact, e.g., by a first time shift past the lift-off of the contact. For example, lift-off of the contact occurs at a point in time indicated by t lift-off . In some embodiments, a characteristic intensity value I C  at lift-off is determined from a point on shifted intensity profile  5116  corresponding to a time t lift-off  when lift-off of contact from touch screen  112  is detected (e.g., the time when detected intensity  5114  drops to a contact intensity value of 0). In some embodiments, an initial speed for moving content (e.g., v 1 , v 3 , v 5  as indicated in  FIG. 5FF, 5JJ, 5NN , respectively) and/or a steady state speed for scrolling through the content to the predefined portion (e.g., scrolling to the end of content  592  as indicated by scroll position indicator  596  in  5 RR) are determined based on a selected intensity value (e.g., I C ) on the shifted intensity profile  5116 . 
       FIG. 5TT  illustrates a speed filter, in accordance with some embodiments. Solid line  5118  indicates a detected speed of a contact. Dotted line  5120  indicates a shifted speed profile that indicates filtered speed values based on the detected speed values indicated by detected speed  5118 . The speed filter shifts a speed profile of a contact, e.g., by a first time shift past the lift-off of the contact. For example, lift-off of the contact occurs at a point in time indicated by t lift-off . In some embodiments, a characteristic speed value V C  at lift-off is determined from a point on shifted speed profile  5120  corresponding to a time t lift-off  when lift-off of contact from touch screen  112  is detected (e.g., the time when detected speed  5118  drops to a contact speed value of 0). In some embodiments, an initial speed for moving content (e.g., v 1 , v 3 , v 5  as indicated in  FIG. 5FF, 5JJ, 5NN , respectively) and/or a steady state speed for scrolling through the content to the predefined portion (e.g., scrolling to the end of content  592  as indicated by scroll position indicator  596  in  5 RR) are determined based on a selected speed value (e.g., V C ) on the shifted speed profile  5120 . 
       FIGS. 6A-6B  are flow diagrams illustrating a method  600  of navigating within and between content items in accordance with some embodiments. The method  600  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. In some embodiments, the display is a touch-screen display and the touch-sensitive surface is on or integrated with the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  600  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, the method  600  provides an efficient way to navigate within and between content items based on the intensity of a user input. Such methods reduce the number, extent, and/or nature of the inputs from a user and produce a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to interact with the content item faster and more efficiently conserves power and increases the time between battery charges. 
     In some embodiments, method  600  is performed at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. 
     The device displays ( 602 ), on the display, content of a first content item, wherein the first content item is one of a sequence of content items (e.g., a plurality of content items). 
     In some embodiments, the sequence of content items corresponds ( 604 ) to a plurality of electronic messages in an electronic messaging application (e.g., as shown in  FIG. 5J ), a plurality of web browser windows (or tabbed windows) in a web browser, a plurality of applications, a plurality of digital images in a set of images (e.g., a single album or collection in a photo or camera application), or a plurality of sets of digital images (e.g., a plurality of albums or collections of photos in a photo or camera application). In some embodiments, the sequence of content items corresponds to a plurality of content sections, such as a plurality conversations in a messaging or email application, a plurality of weeks (or months or years) in a calendar application, a plurality of chapters in a book, a plurality of scenes in a video, or a plurality of events in a digital image library. 
     The device detects ( 606 ) a user input that includes movement of a contact in a respective direction on the touch-sensitive surface. In some embodiments, the user input is a swipe gesture that is made with the contact (e.g., user input  510 ,  FIGS. 5B-5C  and/or user input  513 ,  FIGS. 5E-5G ). In some embodiments, the swipe gesture includes movement of the contact from a first location on the touch-sensitive surface to a second location on the touch-sensitive surface. In some embodiments, the swipe gesture is a vertical swipe gesture. In some embodiments, the swipe gesture is a horizontal swipe gesture. 
     In response ( 608 ) to detecting the user input: in accordance with a determination that the user input meets item-switching criteria, the device replaces display of the first content item with display of a second content item (e.g., a different content item distinct from the first content item) in the sequence of content items, wherein the item-switching criteria include a criterion that is met when a characteristic intensity (e.g., a maximum intensity) of the contact is above a first intensity threshold (e.g., user input  513 ,  FIGS. 5E-5G  results in replacing display of content item  502  with display of second content  518 ). 
     In some embodiments, the item-switching criteria also include a criterion that is met when the device detects a predetermined magnitude (e.g., amount or distance) of movement of the contact (e.g.,  FIG. 5E  shows movement of user input  513  as a precondition to replacing display of content item  502  with display of second content  518 ). That is, there is a predetermined magnitude of movement that is required to be detected by the device in order to cause the device to replace display of the first content item with display of the second content item. In some embodiments, slight movement of the contact (e.g., less than the predetermined magnitude) results in display of a portion of the second content item and the device then reverts back to displaying the first content item when the contact terminates. 
     In some embodiments, when an initial intensity of the contact does not exceed the first intensity threshold (e.g., IT L  in  FIG. 5B ), the device scrolls the first content item in response to the initial user input (e.g., an initial portion of a swipe gesture). If later during the user input, the contact exceeds the first intensity threshold, the device then transitions to displaying the second content item. In some embodiments, the item-switching criteria are met when the initial intensity of the contact exceeds the first intensity threshold. In some embodiments, the item-switching criteria are met when the initial intensity of the contact exceeds the first intensity threshold while the contact is moving (e.g., moving above a predetermined velocity threshold). In some embodiments, the item-switching criteria are not met if the contact is stationary or is moving below a predetermined velocity threshold, even if the characteristic intensity of the contact exceeds the first intensity threshold. 
     In response ( 608 ) to detecting the user input: in accordance with a determination that the user input does not meet the item-switching criteria, the device navigates through the content of the first content item in accordance with the movement of the contact (e.g., displaying a second portion of the first content that is different from the first portion of the content, as shown in  FIGS. 5A-5C ). 
     In some embodiments, the item-switching criteria includes ( 610 ) a criterion that is met when the characteristic intensity of the contact exceeds the first intensity threshold after detecting at least a predetermined threshold amount of movement of the contact. For example when an increase in intensity from below the first intensity threshold to above the first intensity threshold is detected before the user starts swiping (e.g., before the device detects movement of the contact), the device does not switch between content items. Conversely, in this example, when the increase in intensity from below the first intensity threshold to above the first intensity threshold is detected during the swipe, the device navigates to the second content item). 
     In some embodiments, the second content item is ( 612 ) sequentially adjacent to the first content item (e.g. in the sequence of content items) and is selected based on the respective direction of the movement of the contact. In some embodiments, replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item. The transition includes concurrently displaying at least a portion of the first content item and at least a portion of the second content item and the transition is dynamically controlled by the user input. 
     In some embodiments, replacing display of the first content item with a second content item in the sequence of content items includes sliding the first content item off the display in a direction corresponding to the respective direction and sliding the second content item onto the display in the direction corresponding to the respective direction. For example, when the movement of the contact is principally vertically upwards, the first content item is slid off the display vertically upwards toward the top of the display and the second content item is slid onto the display vertically upwards from the bottom of the display. In some embodiments, a vertically upward swipe results in forward navigation in the sequence of content items (e.g. when the first content item is a photograph, forward navigation results in display of another photograph that is more recent than the first photograph) or vice versa. As another example, when the movement of the contact is principally vertically downwards, the first content item is slid off the display vertically downwards toward the bottom of the display and the second content item is slid onto the display vertically downwards from the top of the display. In some embodiments, a vertically downwards swipe results in backward navigation in the sequence of content items (e.g. when the first content item is a photograph, backward navigation results in display of another photograph that is less recent than the first photograph) or vice versa. In some embodiments, the device performs analogous functionality with respect to horizontal swipes. For example, a rightward-swipe results in backward navigation with left-to-right sliding, and a leftward swipe results in forward navigation with right-to-left sliding or vice versa. 
     In some embodiments, replacing display of the first content item with a second content item includes directly manipulating the first content item and the second content item in accordance with the movement of the contact. For example, the movement (e.g., speed, direction, and/or position) of the first content item and the second content item, when sliding on and off the display as described above, corresponds to (e.g. tracks) the movement of the contact so that the user feels that she is directly dragging the second content item onto the display and pushing the first content item off the display. 
     In some embodiments, navigating through the content of the first content item includes: in accordance with a determination that the respective direction is a first direction on the touch-sensitive surface, scrolling ( 614 ) the content in a first direction on the display; and in accordance with a determination that the respective direction is a second direction on the touch-sensitive surface, scrolling the content in a second direction on the display that is different from the first direction on the display. In some embodiments, navigating through the content of the first content item includes directly manipulating the displayed content of the first content item in accordance with the movement of the contact. For example, the movement (e.g., speed, direction, and/or distance) of the content, when scrolled, tracks the movement of the contact. In some embodiments, the scrolling occurs in the same direction as the sliding of content items on and off the display that would have occurred, as described above, had the user input met the item-switching criteria. So, for example, a vertically upwards swipe that is below the first intensity threshold results in upward scrolling of the first content item, while a vertically upward swipe that is above the first intensity threshold results in sliding the first content item upwards off the top of the display and sliding the second content item upwards from the bottom of the display. 
     In some embodiments, navigating through the content of the first content item in accordance with the movement of the contact includes: maintaining ( 616 ) display of a first portion of the first content item in a first user interface region on the display; and navigating (e.g., scrolling) through a second portion of the first content item in a second user interface region on the display. In some embodiments, when scrolling the content within a content item, a portion of the content item (e.g., an email header or universal resource locator (URL) bar) is fixed relative to the content (e.g., the body of the content), whereas when switching between the content items, the whole first content item (e.g., both the first portion of the first content item and the second portion of the first content item) scrolls with the content. For example, when switching between the content items, an email header and/or URL bar scroll with the corresponding content item. 
     In some embodiments, replacing display of the first content item with the second content item includes displaying ( 618 ) a transition between the first content item and the second content item; and the transition includes reducing a size of the first content item. For example, the transition includes zooming out from the first content item at the start of the transition to indicate to the user that the device is navigating to the second content item rather than navigating (e.g., scrolling) within the first content item. In some embodiments, the progress of the transition is directly controllable by the user, e.g., via the intensity of the contact. So, for example, as the user increases the contact intensity toward the first intensity threshold, the first content item zooms-out. If the user subsequently reduces the intensity of the contact slightly, the first content item zooms back in. In some embodiments, a plurality of intensity levels within the vicinity of the first intensity threshold map to a plurality of corresponding zoom levels (e.g., sizes) of the first content item. Thus, the user feels as though she is pushing the first content item back in the z-direction by pushing harder on the contact. In some embodiments, as a result of reducing the size of the first content item, a region beyond an edge of the first content item is displayed (e.g., a background area that is a different color or pattern than a color or pattern of the background of the first content item, illustrating to the user that the first content item has been pushed back in the z-direction, as shown in  FIG. 5E ). 
     In some embodiments, replacing display of the first content item with the second content item includes displaying ( 620 ) a transition between the first content item and the second content item; and the transition includes increasing a size of the second content item (e.g., zooming in on the second content item at the end of the transition to indicate that navigation to the second content item is complete). In some embodiments, the progress of the transition is directly controllable by the user, e.g., via the intensity of the contact. So, for example, as the user reduces the contact intensity toward the first intensity threshold, the second content item zooms-in. If the user subsequently increases the intensity of the contact slightly, the second content item zooms back out. In some embodiments, a plurality of intensity levels within the vicinity of the first intensity threshold map to a plurality of corresponding zoom levels (e.g., sizes) of the second content item. For example, the increase in intensity of the contact from below the first intensity threshold to above the first intensity threshold causes the device to push the first content item back. Movement of the contact then drags the second content item onto the display and pushes the first content item off of the display, where both the first content item and the second content item are zoomed-out during dragging (e.g., scrolling). When the second content item is scrolled onto (e.g., entirely onto the display, or past a predefined threshold for transitioning to the second content item), the second content item increases in size when the intensity is reduced from above the first intensity threshold to below the first intensity threshold, or when liftoff of the contact is detected, as shown in  FIGS. 5G-5I . 
     In some embodiments, while displaying the first content item, the device detects ( 622 ) a second user input at a location that corresponds to a selectable affordance (e.g., a URL link, data detected text, or an icon), wherein the second user input includes a second contact that is stationary on the touch-sensitive surface. In response to detecting the second user input, in accordance with a determination that the user input occurs while a focus selector is at a location that corresponds to a selectable affordance (e.g., a URL link, data detected text, or an icon) and the movement of the contact is less than a predetermined amount (e.g., the contact is stationary or nearly so), the device displays a preview area of content that corresponds to the selectable affordance overlaid on the first content item. In some embodiments, the device determines whether the contact is moving on the touch-sensitive surface (e.g., the contact moves more than a predetermined amount in a predetermined time) or whether the contact is stationary (e.g., the contact moves less than a predetermined amount in a predetermined time) on the touch-sensitive surface. When the contact is moving, the device either navigates through the content of the first content item or replaces display of the first content item with the second content item depending on whether the user input meets item-switching criteria, as described above. However, when the contact is stationary and occurs on or over a selectable affordance, the device displays a preview (e.g., peeks at a second user interface that corresponds to the selectable affordance via a preview window). 
     In some embodiments, in accordance with a determination that the user input begins at a first edge of the touch-sensitive surface (e.g., the user input is a flick gesture that starts at the edge of the touch-sensitive surface, sometimes called an “edge swipe”), the device performs ( 624 ) an operation that is distinct from both replacing display of the first content item with the second content item and navigating through the content of the first content item. For example, for a web browser, the operation includes displaying a web page from the history of web pages viewed in the window/tabbed window of the web browser; for an electronic messaging program, the operation includes displaying (e.g., in sequence) a plurality of representations of electronic communications; for a social networking application, the operation includes displaying a menu with settings for the application.) In some embodiments, in accordance with a determination that the user input begins at a first edge of the touch-sensitive surface (e.g., the user input is a flick gesture that starts at the edge of the touch-sensitive surface) and has a characteristic intensity above a respective intensity threshold, the device performs a different operation that is distinct from any of replacing display of the first user interface with the second user interface, displaying the second portion of the first user interface, or an operation that is performed when the characteristic intensity is below the respective threshold. For example, in response to detecting an edge-swipe with an intensity above the respective threshold, the device displays a multitasking user interface for switching between open applications). 
     In some embodiments, after replacing display of the first content item with the second content item in the sequence of content items, detecting a second user input that includes movement of a second contact on the touch-sensitive surface; in response to detecting the second user input: in accordance with a determination that the second user input meets the item-switching criteria, the device replaces ( 626 ) display of the second content item with a third content item in the sequence of content items; and in accordance with a determination that the second user input does not meet the item-switching criteria, navigating through content of the second content item in accordance with the movement of the second contact. 
     It should be understood that the particular order in which the operations in  FIGS. 6A-6B  have been described is merely exemplary and is not intended to indicate that the described order is the only order in which the operations could be performed. One of ordinary skill in the art would recognize various ways to reorder the operations described herein. Additionally, it should be noted that details of other processes described herein with respect to other methods described herein (e.g., methods  700 ,  800 ,  900 , and  1000 ) are also applicable in an analogous manner to method  600  described above with respect to  FIGS. 6A-6B . For example, the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, and animations described above with reference to method  700  optionally have one or more of the characteristics of the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, and animations described herein with reference to other methods described herein (e.g., methods  700 ,  800 ,  900 , and  1000 ). For brevity, these details are not repeated here. 
       FIGS. 7A-7C  are flow diagrams illustrating a method  700  of reordering list items in accordance with some embodiments. The method  700  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. In some embodiments, the display is a touch-screen display and the touch-sensitive surface is on or integrated with the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  700  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, the method  700  provides an intuitive way to reorder list items. The method reduces the number, extent, and/or nature of the inputs from a user when reordering list items, thereby creating a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to reorder list items faster and more efficiently conserves power and increases the time between battery charges. 
     The device presents ( 702 ) a first portion of a list of items  532  on the display. For example, a list of items  532  includes items  534 ,  536 ,  538 ,  540 ,  542 ,  544 ,  546 , and  548 , as indicated at  5 L- 5 U. In  FIG. 5L , a portion of the list of items  532  is presented on touch screen  112 . The portion of the list of items shown in  FIG. 5L  includes items  534 ,  536 ,  538 ,  540 ,  542 , and  544 . 
     The device detects ( 704 ) a contact on the touch-sensitive surface  112  while the first portion of the list of items  532  is presented on the display (e.g., while a focus selector is over a first item in the list of items). For example, a contact is detected on touch screen  112  at a location indicated by focus selector  550  while the first portion of the list of items  532  (including items  534 - 544 ) is presented on touch screen  112 , as shown in  FIG. 5M . Focus selector  550  is over item  534  of list  532 . 
     The device detects ( 706 ) a first movement of the contact on the touch-sensitive surface  112  while a characteristic intensity of the contact remains below a first intensity threshold. The first intensity threshold is, e.g., hint intensity level IT H , light press intensity level IT L , or another statically or dynamically determined intensity level. For example, in  FIG. 5M , the contact at the location indicated by focus selector  550  moves on touch screen  112 , as indicated by arrow  552 , while the characteristic intensity of the contact remains below IT H , as indicated by intensity level meter  530 . 
     In response to detecting the first movement of the contact on the touch-sensitive surface  112  while the characteristic intensity of the contact remains below the first intensity threshold (e.g., below IT H ), the device scrolls ( 708 ) the list of items  532  to present a second portion of the list of items  532  on the display in accordance with the first movement of the contact on the touch-sensitive surface (e.g., as in regular scrolling with a light drag). For example, in response to the movement of the contact along the path indicated by arrow  552 , list  532  is scrolled to present a second portion of the list including items  546  and  548 , as indicated in  FIG. 5N . To indicate that scrolling has occurred, scroll position indicator  554  is shown at a higher position in the user interface of  5 N than the position of scroll position indicator  554  in the user interface of  5 M. 
     While a focus selector  550  associated with the contact is located on a first item (e.g., item  534 ) in the second portion of the list of items presented on the display (and while continuing to detect the contact on the touch-sensitive surface), the device detects ( 710 ) an increase in the characteristic intensity of the contact above the first intensity threshold (e.g., IT H  as shown at intensity meter  530 ) followed by a second movement of the contact on the touch-sensitive surface. For example, while focus selector  550  is located on item  534  of the second portion of the list of items  532 , as shown in  FIG. 5O , a characteristic intensity of the contact increases above IT H , as shown at intensity meter  530 , followed by a movement of the contact along the path indicated by  556 . 
     In response to detecting the increase in the characteristic intensity of the contact above the first intensity threshold followed by the second movement of the contact on the touch-sensitive surface, the device moves ( 712 ) the first item (e.g., item  534 ) relative to other items in the second portion of the list of items  532  presented on the display in accordance with the second movement of the contact (e.g., detaching an item from the list and moving it with a drag that started with a deep press). For example, as shown at  FIGS. 5P-5S , in response to the increase in the characteristic intensity of the contact above the first intensity threshold (e.g., above IT H , as shown by intensity meter  530  as shown in  FIG. 5O , above IT L , as shown by intensity meter  530  as shown in  FIG. 5P , above deep press intensity level IT D , or above another statically or dynamically determined intensity threshold level) followed by movement of the contact along the path indicated by arrow  556 , first item  534  moves relative to other items  536 ,  538 ,  540 ,  546 , and  548  in the second portion of the list of items  532 . 
     In some embodiments, in response to detecting the increase in the characteristic intensity of the contact above the first intensity threshold followed by the second movement of the contact on the touch-sensitive surface, while the focus selector  550  associated with the contact is located on the first item (e.g., item  534 ) in the second portion of the list of items  532 , the device changes ( 714 ) an appearance of the first item (e.g., enlarging the first item, highlighting a boundary of the first item, changing the color or hue of the first item, lifting the first item above the plane of the list of items, or providing a combination of two or more of the above visual effects, while maintaining the normal appearances of the other items in the list). For example, as shown in  FIGS. 5O-5S , in response to the increase in the characteristic intensity of the contact above the first intensity threshold (e.g., above IT H , as shown by intensity meter  530  as shown in  FIG. 5O , or above IT L , as shown by intensity meter  530  as shown in  FIG. 5P ) followed by movement of the contact along the path indicated by arrow  556 , while focus selector  550  is located on item  534  in the second portion of list  532 , the appearance of item  534  is changed. For example, a highlighted boundary is shown around item  534 , as shown in  FIGS. 5O-5S . When item  534  is detached from list  532 , as shown in  FIGS. 5P-5S , the size of item  534  is reduced and item  534  is shown lifted above the plane of the list of items  532 . In some embodiments, the appearance of the whole list may also change in a different way, so that the appearance change of the first item is still distinguished from the appearance change applied to the other items in the list. In some embodiments, as the characteristic intensity of the contact continues to vary above the first intensity threshold, the amount of appearance change is dynamically determined and adjusted based on the actual variation in the characteristic intensity of the contact. 
     In some embodiments, changing the appearance of the first item (e.g., item  534 ) includes ( 716 ) dynamically changing a size of the first item in accordance with the characteristic intensity of the contact (e.g., dynamically increasing the size of the first item as the current intensity of the contact increases beyond the first threshold, such that the first item overlaps with an item adjacent to the first item). For example, when the characteristic intensity of the contact at the position indicated by focus selector  550  increases from a level above hint intensity threshold IT H , as shown by intensity meter  530  in  FIG. 5O , to a level above light press intensity threshold IT L , as shown by intensity meter  530  in  FIG. 5P , the size of item  534  decreases from the size of item  534  as shown in  FIG. 5O  to the size of item  534  as shown in  FIG. 5P . 
     In some embodiments, in accordance with the second movement of the contact on the touch-sensitive surface, the device moves ( 718 ) the first item (e.g., item  534 ) by a first distance relative to a second item (e.g., item  536 ) that is adjacent to the first item to at least partially reveal a first item slot (e.g., item  558 ) associated with the first item on the display. For example, as shown in  FIGS. 5P-5R , in accordance with the movement of the contact on touch screen  112  along the path indicated by arrow  556 , item  534  moves relative to item  536  to partially reveal item slot  558  associated with  534 . 
     In some embodiments, moving the first item (e.g., item  534 ) by the first distance relative to the second item (e.g., item  536 ) that is adjacent to the first item includes ( 720 ), during an initial portion of the second movement of the contact (e.g., during the first 10 mm or 5 mm of the second movement of the contact after the intensity of the contact has reached above the first intensity threshold), moving the first item at a slower speed than the focus selector  550  to create a distance lag between the first item and the focus selector (e.g., the first item is dragged behind the focus selector with some inertia); and during a subsequent portion of the second movement of the contact following the initial portion of the second movement of the contact (e.g., after the first 10 mm or 5 mm of the second movement of the contact after the intensity of the contact has reached above the first intensity threshold), accelerating the movement of the first item to eliminate the distance lag between the first item and the focus selector (e.g., during the next 2 mm or 1 mm of the second movement of the contact after the initial portion of the second movement on the contact, the first item quickly snaps to the focus selector, and moves together with the focus selector for the remainder of the second movement). For example, during an initial portion of the movement of the contact along the path indicated by arrow  556 , as shown in  FIGS. 5P-5Q , item  534  moves at a slower speed than focus selector  550  (e.g., the position of focus selector  550  in  FIG. 5P  is different from the position of focus selector  550  in  FIG. 5Q  and the position of item  534  in  FIG. 5P  is the same as the position of item  534  in  FIG. 5Q ). During a subsequent portion of the movement of the contact along the path indicated by arrow  556 , as shown in  FIGS. 5Q-5R , the movement of item  534  accelerates to eliminate the distance lag between item  534  and focus selector  550  (e.g., item  534  moves from a position as shown in  FIG. 5Q  with focus selector  550  at the lower edge of item  534  to a position as shown in  FIG. 5R  with focus selector  550  centered on item  534 , such that item  534  has “caught up” with focus selector  550 ). 
     In some embodiments, the device detects ( 722 ) a lift-off of the contact upon moving the first item (e.g., item  534 ) by the first distance relative to the second item (e.g., item  536 ) that is adjacent to the first item; and, in accordance with a determination that the first distance is smaller than a first threshold distance (e.g., half of a slot height), the device restores the first item into the first item slot (e.g. item slot  558 ) associated with the first item on the display (e.g., and reversing visual changes applied to the first item and/or other items in the list, such as restoring the size, transparency, etc. of the first item and/or other items in the list). For example, item  534  is restored into item slot  558  (e.g. the location of item  534  before item  534  detached from list  532 ), resulting in a user interface that displays a list  532  that is the same as list  532  shown in  FIG. 5N . 
     In some embodiments, in accordance with a determination that the first distance is greater than a first threshold distance (e.g., half of a slot height), the device moves ( 724 ) the second item into the first item slot associated with the first item to reveal a second item slot (e.g. item slot  560 ) associated with the second item (e.g., sliding the second item into a slot that was associated with the first item). For example, as shown in  FIG. 5S , item  536  is moved into first item slot  558  (in which item  534  was previously located) and second item slot  560  (in which item  536  was previously located) is revealed. 
     In some embodiments, the device detects ( 726 ) a lift-off of the contact while the second item slot (e.g. item slot  560 ) associated with the second item (e.g., item  536 ) is revealed on the display; and in response to detecting the lift-off of the contact while the second item slot associated with the second item is revealed on the display, the device inserts the first item (e.g.  534 ) into the second item slot. For example, as shown in FIG.  5 T 1 , first item  534  is inserted into item slot  560  (that was previously occupied by item  536 ). 
     In some embodiments, during the second movement of the contact, for a plurality of other items besides the first item in the list of items, the device moves ( 728 ) a respective other item to a respective new item slot and reveals a respective previous item slot for the respective other item on the display. For example, as a movement of the contact that causes item  534  to pass over multiple other items (e.g., over items  536  and  538 ) occurs, item  536  is moved to item slot  558  and item slot  560  for item  536  is revealed; and subsequently item  538  is moved to item slot  560  and a new item slot (not shown) is revealed. 
     In some embodiments, the device generates ( 730 ) a respective tactile output (e.g., thereby providing haptic feedback) as the respective other item moves to the respective new item slot and reveals the respective previous item slot (e.g., the tactile output is feedback indicating that the respective other item has snapped into a new slot). For example, as shown in  FIG. 5S , when item  536  moves to item slot  558  and item slot  560  is revealed, a tactile output, as indicated at  562 , occurs. 
     In some embodiments, a respective movement of the respective other item changes ( 732 ) in accordance with the characteristic intensity of the contact during the second movement of the contact. For example, the movement of the respective other item slows down when the contact intensity increases. As a result, the scrolling of the other items in the list during the movement of the first item slows down when the intensity of the contact increases during the second movement of the contact. 
     In some embodiments, the device detects ( 734 ) that the first item (e.g. item  534 ) has moved within a second threshold distance of a first end (e.g., top or bottom) of the displayed second portion of the list of items in accordance with the second movement of the contact; and, in response to detecting that the first item has moved within the second threshold distance of the first end of the displayed second portion of the list of items, the device scrolls the list of items toward a second end (e.g., bottom or top) of the displayed second portion of the list of items opposite the first end to display a third portion of the list of items. For example, as shown in FIG.  5 T 2 , item  534  moves along a path indicated by arrow  564  to a location within a threshold distance of lower edge  566  of the displayed portion of list  532 . The list of items  532  is scrolled toward upper edge  568 , as shown in FIGS.  5 T 2 - 5 U. In  5 U, items  542  and  544  are revealed. To indicate that scrolling has occurred, scroll position indicator  554  is shown at a lower position in the user interface of  5 U than the position of scroll position indicator  554  in the user interface of  5 T 2 . 
     In some embodiments, scrolling the list of items  532  toward the second end (e.g., toward upper edge  568 ) of the displayed second portion of the list of items opposite the first end (e.g., lower edge  566 ) to display the third portion of the list of items includes ( 736 ): dynamically changing a scrolling speed of the scrolling toward the second end of the displayed second portion of the list of items in accordance with the characteristic intensity of the contact. In some embodiments, increasing the intensity of the contact causes the scrolling of the list of items to speed up, e.g., to quickly scroll to the desired location in the list for inserting the first item. In some embodiments, increasing the intensity of the contact causes the scrolling of the list of items to slow down, e.g., to allow the user to see more clearly which items are coming into view. 
     In some embodiments, the device applies ( 738 ) a transparency effect to the first item (e.g., making the first item semitransparent) while the first item (e.g. item  734 ) overlaps with another item in the list of items (e.g., item  736 ). 
     It should be understood that the particular order in which the operations in  FIGS. 7A-7C  have been described is merely exemplary and is not intended to indicate that the described order is the only order in which the operations could be performed. One of ordinary skill in the art would recognize various ways to reorder the operations described herein. Additionally, it should be noted that details of other processes described herein with respect to other methods described herein (e.g., methods  600 ,  800 ,  900 , and  1000 ) are also applicable in an analogous manner to method  700  described above with respect to  FIGS. 7A-7C . For example, the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, and animations described above with reference to method  700  optionally have one or more of the characteristics of the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, and animations described herein with reference to other methods described herein (e.g., methods  600 ,  800 ,  900 , and  1000 ). For brevity, these details are not repeated here. 
       FIGS. 8A-8C  are flow diagrams illustrating a method  800  of navigating structured content in accordance with some embodiments. The method  800  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. In some embodiments, the display is a touch-screen display and the touch-sensitive surface is on or integrated with the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  800  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, the method  800  provides an intuitive way to navigate structured content. The method reduces the number, extent, and/or nature of the inputs from a user when navigating structured content, thereby creating a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to navigate structured content faster and more efficiently conserves power and increases the time between battery charges. 
     The device presents ( 802 ) a first portion of structured content  572  on the display, wherein the structured content  572  includes a plurality of sections, and the first portion includes content from a first section of the plurality of sections. For example, structured content  572  (e.g., the book  The Jungle Book  by Rudyard Kipling), as illustrated in  FIGS. 5V-5CC  includes multiple sections (e.g., chapters).  FIG. 5V  shows a portion including content from Chapter 3 of structured content  572 . 
     The device detects ( 804 ) a first contact on the touch-sensitive surface while the first portion of the structured content is presented on the display. For example, as shown at  FIGS. 5W-5BB , a contact is received at a location indicated by focus selector  574 . 
     The device detects ( 806 ) an increase in a characteristic intensity of the first contact on the touch-sensitive surface (e.g., an increase from below hint intensity threshold IT H  to above IT H , as indicated at  FIGS. 5Y-5Z  and/or an increase from below light press intensity threshold IT L  to above IT L , as indicated at  FIGS. 5Z-5AA ) and detects a first movement of the first contact on the touch-sensitive surface (e.g., a movement along a path indicated by arrow  580  in  FIGS. 5Z-5BB ). In some embodiments, detection of the movement of the contact is required before detection of the increase in the characteristic intensity of the contact (e.g., to differentiate from a gesture for triggering a peek and pop response of the user interface). In some embodiments, detection of an increase in the characteristic intensity of the contact is required before detection of the movement of the contact. In some embodiments there is no relative timing requirement for detecting the increase in contact intensity and detecting the movement of the contact. 
     In response to detecting the increase in the characteristic intensity of the first contact and detecting the first movement of the first contact ( 808 ): in accordance with a determination that the characteristic intensity of the contact increases above a first intensity threshold (e.g., above intensity light press intensity threshold IT L , or another statically or dynamically determined threshold), the device translates the structured content  572  to display a start of a second section adjacent to the first section of the structured content at a predefined location on the display (e.g., the device translates the structured content to display at the beginning of the UI window or the middle of the UI window). For example,  FIGS. 5AA-5BB  illustrate a translation of structured content  572  from displaying a portion of a first section (Chapter 3, as shown in  FIG. 5AA ) to displaying a start of an adjacent section (Chapter 4, as shown in  FIG. 5BB ). In some embodiments, the predefined location on the display is chosen independent of the structured content and/or the movement of the contact. In accordance with a determination that the characteristic intensity of the contact does not increase above the first intensity threshold (e.g., does not exceed light press intensity threshold IT L ), the device translates the structured content  572  in accordance with a magnitude of the movement (e.g., speed or distance) of the contact on the touch-sensitive surface. For example, as shown in  FIGS. 5W-5X , structured content  572  is translated (e.g., from showing a first portion of Chapter 3, as shown in  FIG. 5W , to showing a second portion of Chapter 3, as shown in  FIG. 5X ) in accordance with a distance traversed by focus selector  574  as the contact moves across touch screen  112  along a path indicated by arrow  578 . 
     In some embodiments, during the translating of the structured content to display the start of the second section adjacent to the first section on the display, a focus selector  574  associated with the first contact is on ( 810 ) the structured content  572  (and not on an index or scroll bar presented on the display). For example, as shown in  FIGS. 5AA-5BB , during the translating of the structured content to display the start of the second section (e.g., Chapter 4) adjacent to the first section (Chapter 3), focus selector  574  is located on the structured content  572 . 
     In some embodiments, in response to detecting the increase in the characteristic intensity of the first contact and the first movement of the first contact (e.g., in response to detecting an increase in the characteristic intensity of the first contact above the first intensity threshold, and the first movement of the first contact on the touch-sensitive surface), the device applies ( 812 ) a visual effect on the first portion of the structured content on the display. In some embodiments, applying the visual effect includes shrinking the first portion of the structured content, and/or pushing the first portion of the structured content to a lower z-level on the display. For example, as shown in  FIGS. 5Y-5Z , the displayed portion of structured content  572  is reduced in size (e.g., from the size of the displayed portion of structured content  572  in  FIG. 5Y  to the size of the displayed portion of structured content  572  in  FIG. 5Z ) and pushed to a lower z-level on the display. 
     In some embodiments, the device removes ( 814 ) the applied visual effect on the first portion of the structured content on the display during the translating of the structured content. 
     In some embodiments, prior to the determination that the characteristic intensity of the first contact has increased above the first intensity threshold ( 816 ): the device detects an initial increase in the characteristic intensity of the first contact (e.g., an increase above the first intensity threshold); and, in response to detecting the initial increase in the characteristic intensity of the first contact, the device concurrently presents a scroll bar with the first portion of the structured content  572  on the display, wherein the scroll bar includes a scroll position indicator  576  that indicates a respective position of the first portion of the structured content  572  in the structured content  572 ; and, in response to the determination that the characteristic intensity of the first contact has increased above the first intensity threshold (e.g., IT L ), the device presents a plurality of section indicators (e.g. section indicators  582 ,  584 ,  586 , and  588  as shown in  FIG. 5Z ) along with the scroll position indicator  576 , wherein a relative ordering of the section indicators  582 ,  584 ,  586 , and  588  to the scroll position indicator  576  corresponds to relative positions of the sections to the first portion of the structured content in the structured content  572 . 
     In some embodiments, presenting the plurality of section indicators with the scroll bar includes: presenting ( 818 ) an animation that shows the plurality of section indicators  582 ,  584 ,  586 , and  588  emerging from the scroll position indicator  576  and spreading out along the scroll bar. For example, as illustrated in  FIGS. 5Z-5AA , section indicators  582 ,  584 ,  586 , and  588  spread out from initial positions as shown in  FIG. 5Z  to spread positions as indicated in  FIG. 5AA . In some embodiments, the animation shows the section indicators flying out from the scroll position indicator, overshooting, and then bouncing back to their respective final positions along the scroll bar. 
     In some embodiments, when translating of the structured content to display the start of the second section adjacent to the first section of the structured content, the device presents ( 820 ) an animation that shows the scroll position indicator  576  hopping over a respective section indicator (e.g., section indicator  588 ) in the plurality of section indicators (e.g., the section indicator that is adjacent to the scroll position indicator in the scroll direction). For example, as shown in  FIGS. 5AA-5BB , scroll position indicator  576  hops from above section indicator  588 , as shown in  FIG. 5AA , to below section indicator  588 , as shown in  FIG. 5BB . 
     In some embodiments, the device detects ( 822 ) a lift-off of the first contact, and, in response to detecting the lift-off of the first contact, the device ceases to display the scroll bar, the scroll position indicator, and the plurality of section indicators. For example, as shown in  FIGS. 5BB-5CC , the scroll position indicator  576  and section indicators  582 ,  584 ,  586 , and  588  shown in  FIG. 5BB  are no longer visible when liftoff occurs as shown in  FIG. 5CC . In some embodiments, the scroll bar, the scroll position indicator, and the plurality of section indicators are displayed in response to the determination that the characteristic intensity of the first contact has increased above the first intensity threshold, and if the first movement is detected after the characteristic intensity of the first contact has decreased below the first intensity threshold, the section scrolling mode is not entered, and the plurality of section indicators (and optionally, the scroll bar and the scroll position indicator) are removed from the display. 
     In some embodiments, in response to detecting the lift-off of the first contact, the device presents ( 824 ) an animation that shows the plurality of section indicators (e.g. section indicators  582 ,  584 ,  586 , and  588 , as shown in  FIGS. 5AA-5BB ) moving (e.g., retracting) into the scroll position indicator  576  before ceasing the display the scroll position indicator  576 . 
     In some embodiments, the structured content  572  is translated ( 826 ) to display the start of the second section (e.g., Chapter 4) adjacent to the first section (e.g., Chapter 3) of the structured content at the predefined location on the display in accordance with a determination that the first movement of the first contact (e.g., along the path indicated by arrow  580 ) exceeds a first threshold distance. In some embodiments, if the first movement of the first contact does not exceed the first threshold distance, the structured content is not translated to display the start of the second section adjacent to the first section of the structured content at the predefined location on the display. Instead, the first portion of the structured content remains to be displayed at or is restored to its original location on the display after the first movement. 
     In some embodiments, the characteristic intensity of the first contact is below ( 828 ) the first intensity threshold (e.g., below IT L  as indicated by intensity meter  530 ) after the first movement of the first contact (e.g., along the path indicated by arrow  580 ) exceeds the first threshold distance. For example, the user can release the pressure on the content (e.g., decrease the contact intensity) below the first intensity threshold after entering the section scrolling mode (e.g., entering the section scrolling mode with the increase in intensity above the first intensity threshold and moving the first contact by at least the first threshold distance). Upon reduction of the contact intensity, the device remains in the section scrolling mode, and further movement beyond the first threshold distance is used for continued section scrolling. 
     In some embodiments, the sections in the structured content are mapped ( 830 ) to a plurality of vertical positions on the display (e.g., the plurality of sections correspond to an equal number of positions evenly distributed on the display in the scrolling direction (e.g., the vertical direction). In some embodiments, the vertical positions are represented by respective markers, e.g., section markers (such as section indicators  582 ,  584 ,  586 , and  588 ). In some embodiments, the positions and/or the corresponding markers are located away from the scroll bar, and on the displayed content. In some embodiments, the first movement of the first contact from a first position of the plurality of positions to a second position of the plurality of positions results in a translation of the structured content from one section of the structured document that corresponds to the first position on the display to another section of the structured content that corresponds to the second position on the display. For example, if the structured content has five sections, each section is mapped to a corresponding vertical position on the display along the vertical direction. After the conditions for section scrolling are satisfied and the section scrolling mode has been entered, a movement from the position corresponding to section 3 to the position corresponding to section 5 causes the content to be scrolled from section 3 to section 5, as opposed to causing the content to be scrolled by the amount determined in regular scrolling. In other words, regardless of how many pages are included in section 3 to section 5, a physical movement from the position corresponding to section 3 to the position corresponding to section 5 on the display (e.g., a fixed physical distance), would cause scrolling from section 3 to section 5 in the section scrolling mode. In contrast, in conventional scrolling, the physical distance of the movement of the contact is much more closely correlated with the amount of content scrolling (e.g., lines, pages, etc.) that is performed. 
     It should be understood that the particular order in which the operations in  FIGS. 8A-8C  have been described is merely exemplary and is not intended to indicate that the described order is the only order in which the operations could be performed. One of ordinary skill in the art would recognize various ways to reorder the operations described herein. Additionally, it should be noted that details of other processes described with respect to other methods described herein (e.g., methods  600 ,  700 ,  900 , and  1000 ) are also applicable in an analogous manner to method  800  described above with respect to  FIGS. 8A-8C . For example, the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, animations described above with reference to method  800  optionally have one or more of the characteristics of the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, animations described herein with reference to other methods described herein (e.g., methods  600 ,  700 ,  900 , and  1000 ). For brevity, these details are not repeated here. 
       FIGS. 9A-9D  are flow diagrams illustrating a method  900  of moving content on a display in accordance with some embodiments. The method  900  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. In some embodiments, the display is a touch-screen display and the touch-sensitive surface is on or integrated with the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  900  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, the method  900  provides an intuitive way to move content on a display. The method reduces the number, extent, and/or nature of the inputs from a user when moving content on a display, thereby creating a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to move content on a display faster and more efficiently conserves power and increases the time between battery charges. 
     The device presents ( 902 ) a first portion of content  592  (e.g., “The Raven” by Edgar Allan Poe) on a display (e.g., touch screen  112 ). 
     While presenting the first portion of the content  592  on the display, the device ( 904 ) detects a first contact on a touch-sensitive surface (e.g., touch screen  112 ) and detects a first movement of the first contact on the touch-sensitive surface (e.g., a movement of focus selector  594 , such as a movement along a path indicated by arrow  598  of  FIGS. 5DD-5EE , a movement along a path indicated by arrow  5102  of  FIGS. 5HH-5II , or a movement along a path indicated by arrow  5108  of  FIGS. 5LL-5MM ). 
     In response to detecting the first movement of the first contact, the device scrolls ( 906 ) the content  592  to present a second portion of the content on the display in accordance with the first movement of the first contact. For example, content  592  is scrolled from the first portion of the content displayed in  FIG. 5DD  to present a second portion of the content in  FIG. 5EE . Scrolling to present a second portion of the content  592  is also described with regard to  FIGS. 5II, and 5MM . 
     The device detects ( 908 ) an increase in intensity of the first contact on the touch-sensitive surface during the first movement of the first contact on the touch-sensitive surface. For example, as shown in  FIGS. 5DD-5EE , the intensity of the contact increases above contact detection intensity threshold IT 0 , as indicated by intensity meter  530 , during movement of the contact along a path indicated by arrow  598 . In  FIGS. 5HH-5II , the intensity of the contact increases above light press intensity threshold IT L , as indicated by intensity meter  530 , during movement of the contact along a path indicated by arrow  5102 . In  FIGS. 5LL-5MM , the intensity of the contact increases above light press intensity threshold IT L , as indicated by intensity meter  530 , during movement of the contact along a path indicated by arrow  5108 . 
     After detecting the increase in intensity of the first contact on the touch-sensitive surface during the first movement of the first contact on the touch-sensitive surface, the device detects ( 910 ) a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface. For example, lift-off of the contact is detected, as indicated at  FIG. 5FF , following the movement of the contact indicated in  FIGS. 5DD-5EE . Lift-off of the contact is also detected, as indicated at  FIG. 5JJ , following the movement of the contact indicated in  FIGS. 5HH-5II . Lift-off of the contact is also detected, as indicated at  FIG. 5NN , following the movement of the contact indicated in  FIGS. 5LL-5MM . 
     In response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface, the device moves ( 912 ) the content  592  on the display by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact. For example, content  592  moves in response to lift-off of the contact from a position as indicated at  FIG. 5FF  to a different position as indicated  5 GG. Movement of content  592  in response to lift-off is additionally illustrated at  FIGS. 5JJ-5KK and 5NN-5OO . 
     In some embodiments, the characteristic speed of the first movement is a first speed and moving the content  592  on the display by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes ( 914 ): in accordance with a determination that the characteristic intensity is a first intensity (e.g., a characteristic intensity of the contact below light press intensity threshold IT L , as indicated in  FIGS. 5DD-5EE ), moving the content  592  by a first amount (e.g. movement of content  592  from a position at lift-off as shown in  FIG. 5FF  to a moved position as shown in  FIG. 5GG ); and in accordance with a determination that the characteristic intensity is a second intensity that is different from the first intensity (e.g., an characteristic intensity of the contact above light press intensity threshold IT L , as indicated in  FIGS. 5HH-5II ), moving the content by a second amount that is different from the first amount (e.g. movement of content  592  from a position at lift-off as shown in  FIG. 5JJ  to a moved position as shown in  FIG. 5KK ). The amount of movement of content  592  as shown in  FIGS. 5FF-5GG  is less than the amount of movement of content  592  as shown in  FIGS. 5JJ-5KK . 
     In some embodiments, the first intensity is greater than the second intensity and the first amount of movement is greater than the second amount of movement ( 916 ). For example, the first intensity has a characteristic intensity of the contact above a light press intensity threshold IT L  (e.g., as indicated in  FIGS. 5HH-5II ), the second intensity characteristic intensity of the contact above hint intensity threshold IT H  and below light press intensity threshold IT L  (e.g., as indicated in  FIGS. 5DD-5EE ), and the first amount of movement of content  592  (e.g., as indicated in  FIGS. 5JJ-5KK ) is greater than the second amount of movement of content  593  (e.g., as indicated in  FIGS. 5FF-5GG ). 
     In some embodiments, the first intensity is less than the second intensity and the first amount of movement is greater than the second amount of movement ( 918 ). 
     In some embodiments, moving the content  592  on the display by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes ( 920 ) setting a simulated friction based on the characteristic intensity of the first contact (e.g., decreasing the simulated friction for larger characteristic intensity values). For example, in accordance with a contact that has a characteristic intensity above light press intensity threshold IT L  prior to lift-off (e.g., as indicated in  FIGS. 5HH-5II ), a first simulated friction effect is set, causing a reduction in the velocity of the movement of content  592  from velocity v 3  (as indicated in  FIG. 5JJ ) to velocity v 1  (as indicated in  FIG. 5KK ). In accordance with a contact that has a characteristic intensity above hint intensity threshold IT H  and below light press intensity threshold IT L  (e.g., as indicated in  FIGS. 5DD-5EE ), a second simulated friction effect is set, causing a reduction in the velocity of the movement of content  592  from velocity v 1  (as indicated in  FIG. 5FF ) to velocity v 2  (as indicated in  FIG. 5GG ). In some embodiments, the first simulated friction set when the larger characteristic intensity value of  FIG. 5HH-5II  is detected is decreased in comparison with the second simulated friction set when the smaller characteristic intensity value of  5 DD- 5 EE is detected. 
     In some embodiments, moving the content  592  on the display by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes ( 922 ) setting a simulated inertia based on the characteristic intensity of the first contact (e.g., decreasing the simulated inertia for larger characteristic intensity values). 
     In some embodiments, moving the content on the display by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes ( 924 ) setting an initial speed of movement for moving the content based on the characteristic intensity of the first contact (e.g., increasing the initial speed for larger characteristic intensity values). For example, in accordance with a contact that has a characteristic intensity above light press intensity threshold IT L  prior to lift-off (e.g., as indicated in  FIGS. 5HH-5II ), an initial speed is v 3  (as indicated in  FIG. 5JJ ). In accordance with a contact that has a characteristic intensity above hint intensity threshold IT H  and below light press intensity threshold IT L  prior to lift-off (e.g., as indicated in  FIGS. 5DD-5EE ), an initial speed is v 1  (as indicated in  FIG. 5FF ). In some embodiments, in accordance with the larger characteristic intensity value of  FIGS. 5HH-5II  compared with the characteristic intensity value of  FIGS. 5DD-5EE , v 3  is greater than v 1 . 
     In some embodiments, moving the content  592  on the display by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes ( 926 ): determining an initial speed (e.g., v 1 , v 3 , or v 5  as indicated in  FIGS. 5FF, 5JJ, and 5NN , respectively) for continued scrolling after the lift-off of the first contact based on the characteristic intensity of the first contact (e.g., as indicated by intensity meter  530 ) and the characteristic speed of the first movement detected prior to the lift-off of the first contact and continuing the scrolling of the content  592  after the lift-off of the first contact with the initial speed determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact. In some embodiments, the characteristic intensity and the characteristic speed are intensity and speed detected a predefined time period before the lift-off. In some embodiments, the characteristic intensity is determined based on a filtered intensity profile (e.g.,  5 SS) and/or the characteristic speed is determined based on a filtered speed profile (e.g.,  5 TT). For example, the characteristic values are values on the profiles  5116  and/or  5120  at t lift-off . 
     In some embodiments, in response to detecting the increase in intensity of the first contact on the touch-sensitive surface, the device dynamically applies ( 928 ) a visual effect on the first portion of content  592  on the display in accordance with a current intensity of the first contact on the touch-sensitive surface. For example, dynamically applying the visual effect includes dynamically resizing (e.g., shrinking) the content or changing a z-height (e.g., pushing the content away from the screen) of the content on the display in accordance the current intensity of the first contact. In some embodiments, the visual effect is applied only temporarily when the scroll speed is below a threshold speed (e.g., before the scrolling is started and when the scrolling is just started), and the visual effect is removed when the scrolling speed reaches the threshold speed. 
     In some embodiments, the device presents ( 930 ) a scroll bar on the display, wherein the scroll bar includes a scroll position indicator  596  that indicates a respective position of a currently displayed portion of the content  592  in the content  592 ; and the device presents ( 932 ) a scroll enhancement indicator  5104  concurrently with the scroll position indicator  596 , wherein an appearance of the scroll enhancement indicator  5104  varies dynamically with a current intensity of the first contact on the touch-sensitive surface (e.g., scroll enhancement indicator  5104  is shown with a first length in  FIG. 5HH , when a characteristic intensity of the contact is at above light press intensity threshold IT L , and scroll enhancement indicator  5104  is shown with a second length, greater than the first length in  FIG. 5LL , when a characteristic intensity of the contact is further above light press intensity threshold IT L ). For example, the scroll enhancement indicator is a shadow displayed on a side of the scroll position indicator that is opposite to the scrolling direction, and a length of the shadow dynamically changes in accordance with the intensity of the first contact, e.g., higher intensity leads to a longer shadow. In some embodiments, the length of the shadow also indirectly indicates the amount of deviation (e.g., how much greater an initial scrolling speed after lift-off of contact) as compared to the case in a regular scroll action. In some embodiments, the scroll bar is displayed with a normal touch intensity, and anything beyond the normal touch intensity causes the scroll enhancement indicator to appear as well. 
     In some embodiments, while moving the content  592  on the display by the amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact, the device dynamically changes ( 934 ) the appearance of the scroll enhancement indicator  596  in accordance with a current scrolling speed. For example, scroll enhancement indicator  5104  is shown with a first length in  FIG. 5NN , when a scrolling speed is v 5 , and scroll enhancement indicator  5104  is shown with a second length (shorter than the first length) in  FIG. 5OO , when a scrolling speed is v 6  (v 6  is slower than v 5 , as indicated by the length of arrow  5110  associated with v 6  and with v 5 ). For example, the length of the shadow also indirectly indicates the amount of deviation (e.g., how much greater the current scrolling speed is as compared to the case in a regular scroll action). 
     In some embodiments, the moving the content  592  on the display by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact includes ( 936 ): applying an intensity filter to an intensity profile (e.g.,  5114  of  FIG. 5SS ) of the first contact, wherein the intensity filter shifts the intensity profile (e.g., as shown at  5116  of  FIG. 5SS ) by a first time shift past the lift-off of the first contact (e.g., the intensity filter is a function that skews and shifts the intensity profile to the right on a time-intensity profile) and determining an initial speed (e.g., e.g., v 1 , v 3 , or v 5  as indicated in  FIGS. 5FF, 5JJ, and 5NN , respectively) for moving the content on the display after the lift-off of the first contact based on a selected intensity value on the filtered intensity profile  5116 . For example, the selected intensity value is the intensity value at the time of lift-off on the shifted intensity profile (e.g., I C  on  5116  of  FIG. 5SS ). 
     In some embodiments, moving the content on the display by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact includes ( 938 ): applying a speed filter to a speed profile (e.g.,  5118  of  FIG. 5TT ) of the first contact, wherein the speed filter shifts the speed profile (e.g., as shown at  5120  of  FIG. 5TT ) by a second time shift past the lift-off of the first contact; determining an initial speed (e.g., v 1 , v 3 , or v 5  as indicated in  FIGS. 5FF, 5JJ, and 5NN , respectively) for moving the content on the display after the lift-off of the first contact based on a selected speed value on the shifted speed profile  5120 ; and moving the content on the display with the determined initial speed after the lift-off of the first contact. For example, the selected speed value is the speed value at the time of lift-off on the shifted speed profile (e.g., V C  on  5120  of  FIG. 5TT ). In some embodiments, the selected speed value is greater than the maximum speed of the first contact during the first movement. 
     In some embodiments, prior to detecting the first movement of the first contact, the device detects ( 940 ) an earlier increase in intensity of the first contact while the first contact remains stationary on the touch-sensitive surface. In an example scenario, the device detects the first contact, and then detects an increase in intensity of the first contact while the first contact is stationary on the touch sensitive surface. In this example scenario, even if the device subsequently detects a movement of the first contact (e.g., the first movement of the first contact), as long as the earlier increase in intensity was not detected during the movement, the scrolling is performed in accordance with the first movement, without consideration of the earlier increase in intensity of the first contact while the first contact was stationary. When another increase in intensity is detected while the first contact is moving, then the increase in intensity detected during the movement of the first contact is taken into consideration for the inertia scrolling performed after the lift-off of the first contact, e.g., through the use of the characteristic intensity and characteristic speed of the first contact that were detected during the first movement. 
     In some embodiments, detecting the earlier increase in intensity of the first contact includes ( 942 ) detecting the earlier increase in intensity of the first contact above a first intensity threshold (e.g., a preview intensity threshold, such as hint intensity threshold IT H ) while a focus selector  594  is located on a first user interface element on the display, and the device performs a predefined operation associated with the first user interface element (e.g., presents a preview or a quick action menu associated with the first user interface element) in response to detecting the earlier increase in intensity of the first contact above the first intensity threshold (e.g., a preview intensity threshold) while the focus selector is located on the first user interface element on the display. In an example scenario, the device detects the first contact, and then detects an increase in intensity of the first contact above a first intensity threshold (e.g., a hint intensity threshold IT H  or a preview intensity threshold) while the first contact is stationary on the touch sensitive surface  112  (and correspondingly, and while a focus selector  594  is located on a first user interface element (e.g., a user interface element that is configured to respond to different changes in contact intensity with different user interface responses (e.g., a web link or a representation of a contact, or an application icon) on the display), the device performs a predefined operation associated with the user interface element (e.g., presenting a preview of the webpage referred to in the web link, presenting a quick action menu associated with the contact, or presenting a quick action menu associated with the application icon). After the intensity of the first contact has decreased sufficiently (e.g., decreased below the hint intensity threshold or preview intensity threshold) and before the first contact starts to move, the preview or quick action menus are optionally removed and the user interface is restored to the same state as it was before the increase in contact intensity of the first contact was detected. At this point, the device will resume normal scrolling behavior in accordance with subsequent movement of the first contact (e.g., the first movement of the first contact) without consideration of the earlier increase in intensity of the first contact) detected while the first contact was stationary. When another increase in intensity is detected while the first contact is moving, then the increase in intensity detected during the movement of the first contact is taken into consideration of the inertia scrolling performed after the lift-off of the first contact, e.g., through the use of the characteristic intensity and characteristic speed of the first contact that were detected during the first movement. 
     It should be understood that the particular order in which the operations in  FIGS. 9A-9D  have been described is merely exemplary and is not intended to indicate that the described order is the only order in which the operations could be performed. One of ordinary skill in the art would recognize various ways to reorder the operations described herein. Additionally, it should be noted that details of other processes described herein with respect to other methods described herein (e.g., methods  600 ,  700 ,  800 , and  1000 ) are also applicable in an analogous manner to method  900  described above with respect to  FIGS. 9A-9D . For example, the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, and animations described above with reference to method  900  optionally have one or more of the characteristics of the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, and animations described herein with reference to other methods described herein (e.g., methods  600 ,  700 ,  800 , and  1000 ). For brevity, these details are not repeated here. 
       FIGS. 10A-10C  are flow diagrams illustrating a method  1000  of moving content on a display in accordance with some embodiments. The method  1000  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display, a touch-sensitive surface, and one or more sensors to detect intensity of contacts with the touch-sensitive surface. In some embodiments, the display is a touch-screen display and the touch-sensitive surface is on or integrated with the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  900  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, the method  1000  provides an intuitive way to move content on a display. The method reduces the number, extent, and/or nature of the inputs from a user when moving content on a display, thereby creating a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to move content on a display faster and more efficiently conserves power and increases the time between battery charges. 
     The device presents ( 1002 ) a first portion of content  592  (e.g., “The Raven” by Edgar Allan Poe) on a display (e.g., touch screen  112 ). 
     While presenting the first portion of the content, the device ( 1004 ): detects a first contact (e.g., a contact at a location indicated by focus selector  594 ) on the touch-sensitive surface (e.g., touch screen  112 ); and detects a first movement of the first contact on the touch-sensitive surface (e.g., a movement of focus selector  594 , such as a movement along a path indicated by arrow  5112  of  FIGS. 5PP-5QQ ). 
     The device detects ( 1006 ) a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface. For example, after the movement of the contact indicated by  FIGS. 5PP-5QQ , lift-off of the contact occurs as indicated in  5 RR. 
     In response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface ( 1008 ): in accordance with a determination that the first contact had a characteristic intensity above a respective intensity threshold (e.g., a characteristic intensity above deep press intensity threshold IT D , or another statically or dynamically determined threshold) prior to the lift-off of the first contact, the device scrolls through the content to a predefined portion of the content (e.g., a beginning or an end of the content, or a next section or previous section of the content, depending on the direction of first movement). For example, as indicated in  FIGS. 5PP-5QQ , a characteristic intensity of the contact increased above deep press intensity threshold IT D , as indicated by intensity meter  530 . Accordingly, in  FIG. 5RR , in response to detection of lift-off of the contact, content  592  is scrolled to the end of the content (e.g., as indicated by scroll position indicator  596 ). In accordance with a determination that the first contact had a characteristic intensity below the respective intensity threshold prior to the lift-off of the first contact (e.g., an intensity of the first contact remains below the respective intensity threshold for an entire duration of the first contact), the device scrolls through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement (e.g., scrolling by an amount that is determined based on an initial speed of the content on lift-off of the first contact and simulated inertia and friction). For example, as shown in  FIGS. 5LL-5MM , a characteristic intensity of the contact does not increase above a deep press intensity threshold IT D , as indicated by intensity meter  530 . At  FIGS. 5NN-5OO , in response to detection of lift-off of the contact, content  592  is scrolled (e.g., by an amount that is determined based on a characteristic speed of the contact during the movement along the path indicated by arrow  5108  in  FIGS. 5LL-5MM ). In some embodiments, the initial speed of the content is optionally determined based on a speed of the contact at a predetermined time relative to the lift-off time of the contact. 
     In some embodiments, scrolling through the content to a predefined portion of the content includes ( 1010 ) accelerating scrolling of the content to display an end portion of the content on the display. In some embodiments, the accelerated scrolling to display the end portion of the content is independent of a movement speed of the first movement and/or the length of content that needs to be scrolled to reach the end portion. 
     In some embodiments, the first movement corresponds ( 1012 ) to movement toward a top portion of the display (e.g., as shown in  FIG. 5QQ , the contact moves upward along a path indicated by arrow  5112  toward a top portion of display  112 ). 
     In some embodiments, scrolling through the content to a predefined portion of the content includes ( 1014 ) accelerating scrolling of the content to display a beginning portion of the content on the display. In some embodiments, the accelerated scrolling to display the beginning portion of the content is independent of a movement speed of the first movement and/or the length of content that needs to be scrolled to reach the beginning portion. 
     In some embodiments, the first movement corresponds ( 1016 ) to movement toward a bottom portion of the display. 
     In some embodiments, scrolling through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement includes ( 1018 ): scrolling through the content  592  by a first amount before the lift-off of the first contact (e.g., scrolling from a first position in content  592 , as shown in  FIG. 5PP , to a second position in content  592 , as shown in  FIG. 5QQ ); and continuing to scroll through the content by a second amount after the lift-off of the first contact (e.g., scrolling from the second position in content  592 , as shown in  FIG. 5QQ , to a third position in content  592 , as shown in  FIG. 5RR ), wherein the scrolling of the content after the lift-off of the first contact is continued at an initial speed that is determined based on the characteristic speed of the first contact during the first movement. For example, during the regular scrolling, how much scrolling actually happens depends on factors such as the amount of content that can be scrolled, and the movement speed of the first contact, and does not deterministically scroll to the end or the beginning of the content. 
     In some embodiments, the device detects ( 1020 ) the increase in intensity of the first contact on the touch-sensitive surface above the respective intensity threshold during the first movement of the first contact on the touch-sensitive surface (e.g., the device detects the increase in intensity above deep press intensity threshold IT D , as indicated at intensity meter  530  in  FIGS. 5PP-5QQ ); and in response to detecting the increase in intensity above the respective intensity threshold, the device applies a visual effect on the first portion of content on the display. In some embodiments, the visual effect is an enlargement of the content, or a change in z-height of the content relative to the display plane. 
     In some embodiments, the device removes ( 1022 ) the applied visual effect on the first portion of content on the display during the scrolling through the content to the predefined portion of the content (e.g., during the accelerated scrolling of the content on the display). For example, the visual effect is applied when the intensity is above the first intensity threshold, and during the period of time that the scrolling speed is accelerated to a steady state accelerated scrolling speed, and once the scrolling speed has reached the steady state accelerated scrolling speed, the previously applied visual effect is removed. 
     In some embodiments, the device applies ( 1024 ) an intensity filter to an intensity profile (e.g.,  5114  of  FIG. 5SS ) of the first contact, wherein the intensity filter shifts the intensity profile (e.g., as shown at  5116  of  FIG. 5SS ) by a first time shift past the lift-off of the first contact; and the device determines a steady state speed for the scrolling through the content to the predefined portion of the content based on a selected intensity value on the shifted intensity profile  5116 . For example, the selected intensity value is the intensity value at the time of lift-off on the shifted intensity profile (e.g., I C  on  5116  of  FIG. 5SS ). 
     In some embodiments, the device scrolls ( 1026 ) through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement includes scrolling through the content to display a second portion of the content, and the method includes: while displaying the second portion of the content, detecting a predefined input (e.g., a tap input on the touch-sensitive surface) while a focus selector is within a predefined region (e.g., a predefined top or bottom region of the user interface that is displaying the second portion of the content) on the display; and in response to detecting the predefined input while the focus selector is within the predefined region on the display, scrolling through the content to the predefined portion of the content (e.g., a beginning or an end of the content or a next section or previous section of the content depending on whether the predefined region invoked by the predefined input (e.g., a tap input) is at the top or the bottom of the user interface displaying the second portion of the content). In other words, in some embodiments, the user can quickly scroll to the predefined portion of the content either by a forced press and flick gesture anywhere in the displayed content, or by a tap gesture within the predefined region in the user interface, regardless of how long the content is, and where the displayed portion of the content is within the content. 
     In some embodiments, prior to detecting the first movement of the first contact, the device detects ( 1028 ) an earlier increase in intensity of the first contact above the respective intensity threshold while the first contact remains stationary on the touch-sensitive surface; and the device determines that the first contact had a characteristic intensity below the respective intensity threshold prior to the lift-off of the first contact in accordance with a determination that the intensity of the first contact remained below the respective intensity threshold during the first movement of the first contact on the touch-sensitive surface. In an example scenario, the device detects the first contact, and before detecting the first movement of the first contact, the device detects an increase in intensity of the first contact above the first intensity threshold while the first contact is stationary on the touch sensitive surface. This earlier increase in intensity of the first contact does not affect the user interface responses that occur during or after subsequent movement of the first contact (e.g., the first movement) if the contact intensity had dropped below the first intensity threshold before the start of the movement. In other words, when the device detects a movement of the first contact (e.g., the first movement of the first contact), as long as any increase in intensity above the first intensity threshold was not detected during the movement, the scrolling is performed without consideration of any earlier increase(s) in intensity of the first contact while the first contact was stationary. When an increase in intensity above the first threshold is detected while the first contact is moving, then the device scrolls the content to the predefined portion (e.g., an end or beginning portion). 
     In some embodiments, detecting the earlier increase in intensity of the first contact includes ( 1030 ) detecting the earlier increase in intensity of the first contact above a first intensity threshold (e.g., a preview intensity threshold) while a focus selector is located on a first user interface element on the display, and the device performs a predefined operation associated with the first user interface element (e.g., presenting a preview or a quick action menu associated with the first user interface element) in response to detecting the earlier increase in intensity of the first contact above the first intensity threshold (e.g., a preview intensity threshold) while the focus selector is located on a first user interface element on the display. In an example scenario, the device detects the first contact, and then detects an increase in intensity of the first contact above a first intensity threshold (e.g., a hint intensity threshold or a preview intensity threshold) while the first contact is stationary on the touch sensitive surface (and correspondingly, and while a focus selector is located on a first user interface element (e.g., a user interface element that is configured to respond to different changes in contact intensity with different user interface responses (e.g., a web link or a representation of a contact, or an application icon) on the display). In response to this increase in intensity of the first contact above the first intensity threshold, the device performs a predefined operation associated with the user interface element (e.g., presenting a preview of the webpage referred to in the web link, presenting a quick action menu associated with the contact, or presenting a quick action menu associated with the application icon). Then, after the intensity of the first contact has decreased to below the first intensity threshold (e.g., decreased below the hint intensity threshold or preview intensity threshold) and before the first contact starts to move, the preview or quick action menus are optionally removed and the user interface is restored to the same state as it was before the increase in contact intensity of the first contact was detected. At this point, the device resumes its scrolling behavior in accordance with subsequent movement of the first contact (e.g., the first movement of the first contact) without consideration of the earlier increase in intensity of the first contact detected while the first contact was stationary. When an increase in intensity above the first threshold is detected while the first contact is moving, then the device scrolls the content to the predefined portion (e.g., an end or beginning portion). 
     It should be understood that the particular order in which the operations in  FIGS. 10A-10C  have been described is merely exemplary and is not intended to indicate that the described order is the only order in which the operations could be performed. One of ordinary skill in the art would recognize various ways to reorder the operations described herein. Additionally, it should be noted that details of other processes described herein with respect to other methods described herein (e.g., methods  600 ,  700 ,  800 , and  900 ) are also applicable in an analogous manner to method  1000  described above with respect to  FIGS. 10A-10C . For example, the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, animations described above with reference to method  1000  optionally have one or more of the characteristics of the contacts, gestures, user interface objects, tactile outputs, intensity thresholds, focus selectors, animations described herein with reference to other methods described herein (e.g., methods  600 ,  700 ,  800 , and  900 ). For brevity, these details are not repeated here. 
     In accordance with some embodiments,  FIG. 11  shows a functional block diagram of an electronic device  1100  configured in accordance with the principles of the various described embodiments. The functional blocks of the device are, optionally, implemented by hardware, software, or a combination of hardware and software to carry out the principles of the various described embodiments. It is understood by persons of skill in the art that the functional blocks described in  FIG. 11  are, optionally, combined or separated into sub-blocks to implement the principles of the various described embodiments. Therefore, the description herein optionally supports any possible combination or separation or further definition of the functional blocks described herein. 
     As shown in  FIG. 11 , an electronic device includes a display unit  1102  configured to display content items; a touch-sensitive surface unit  1104  configured to receive user inputs; one or more sensor units  1106  configured to detect intensity of contacts with the touch-sensitive surface unit  1104 ; and a processing unit  1108  coupled to the display unit  1102 , the touch-sensitive surface unit  1104  and the one or more sensor units  1106 . In some embodiments, the processing unit  1108  includes a detecting unit  1110 , a determining unit  1112 , and a display enabling unit  1114 . In some embodiments, the processing unit  1108  is configured to: enable display, on the display unit  1102 , of content of a first content item, wherein the first content item is one of a sequence of content items (e.g., with display enabling unit  1114 ); detect a user input that includes movement of a contact in a respective direction on the touch-sensitive surface unit  1104  (e.g., with detecting unit  1110 ); in response to detecting the user input: in accordance with a determination that the user input meets item-switching criteria (e.g., with the determining unit  1112 ), enable the display unit  1102  to replace display of the first content item with display of a second content item in the sequence of content items (e.g., with the display enabling unit  1114 ), wherein the item-switching criteria include a criterion that is met when a characteristic intensity of the contact is above a first intensity threshold; and, in accordance with a determination that the user input does not meet the item-switching criteria (e.g., with the determining unit  1112 ), enable the display unit  1102  to navigate through the content of the first content item in accordance with the movement of the contact (e.g., with the display enabling unit  1114 ). 
     In some embodiments, the item-switching criteria includes a criterion that is met when the characteristic intensity of the contact exceeds the first intensity threshold after detecting at least a predetermined threshold amount of movement of the contact (e.g., with the detecting unit  1110 ). 
     In some embodiments, the processing unit  1108  is configured to: while enabling display of the first content item (e.g., with the display enabling unit  1114 ), detect a second user input at a location that corresponds to a selectable affordance (e.g., with the detecting unit  1110 ), wherein the second user input includes a second contact that is stationary on the touch-sensitive surface unit  1104 ; in response to detecting the second user input: in accordance with a determination that the user input occurs while a focus selector is at a location that corresponds to a selectable affordance and the movement of the contact is less than a predetermined amount (e.g., with the determining unit  1112 ), enable display of a preview area of content that corresponds to the selectable affordance overlaid on the first content item (e.g., with a display enabling unit  1114 ). 
     In some embodiments, the second content item is sequentially adjacent to the first content item and is selected based on the respective direction of the movement of the contact. 
     In some embodiments, navigating through the content of the first content item includes: in accordance with a determination that the respective direction is a first direction on the touch-sensitive surface unit  1104  (e.g., with the determining unit  1112 ), scrolling the content in a first direction on the display unit  1102  (e.g., with the display enabling unit  1114 ); and in accordance with a determination that the respective direction is a second direction on the touch-sensitive surface unit  1104  (e.g., with the determining unit  1112 ), scrolling the content in a second direction on the display unit  1102  that is different from the first direction on the display unit  1102  (e.g., with the display enabling unit  1114 ). 
     In some embodiments, navigating through the content of the first content item in accordance with the movement of the contact includes: maintaining display of a first portion of the first content item in a first user interface region on the display unit  1102 ; and navigating through a second portion of the first content item in a second user interface region on the display unit  1102  (e.g., with the display enabling unit  1114 ). 
     In some embodiments, replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item (e.g., with the display enabling unit  1114 ); and the transition includes reducing a size of the first content item. 
     In some embodiments, replacing display of the first content item with the second content item includes displaying a transition between the first content item and the second content item (e.g., with the display enabling unit  1114 ); and the transition includes increasing a size of the second content item. 
     In some embodiments, the sequence of content items corresponds to a plurality of electronic messages in an electronic messaging application, a plurality of web browser windows in a web browser, a plurality of applications, a plurality of digital images in a set of images, or a plurality of sets of digital images. 
     In some embodiments, the processing unit  1108  is configured to: in accordance with a determination that the user input begins at a first edge of the touch-sensitive surface unit  1104  (e.g., with the determining unit  1112 ), perform an operation that is distinct from both replacing display of the first content item with the second content item and navigating through the content of the first content item (e.g., with the display enabling unit  1114 ). 
     In some embodiments, the processing unit  1108  is configured to: after replacing display of the first content item with the second content item in the sequence of content items, detect a second user input that includes movement of a second contact on the touch-sensitive surface unit  1104  (e.g., with the detecting unit  1110 ); enable the display unit  1102  to, in response to detecting the second user input: in accordance with a determination that the second user input meets the item-switching criteria, replace display of the second content item with a third content item in the sequence of content items (e.g., with the display enabling unit  1114 ); and in accordance with a determination that the second user input does not meet the item-switching criteria, navigate through content of the second content item in accordance with the movement of the second contact (e.g., with the display enabling unit  1114 ). 
     The operations in the information processing methods described above are, optionally implemented by running one or more functional modules in information processing apparatus such as general purpose processors (e.g., as described above with respect to  FIGS. 1A and 3 ) or application specific chips. 
     The operations described above with reference to  FIGS. 6A-6B  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 11 . For example, detection operation  606 , and replace and navigation operations of operation  608  are, optionally, implemented by event sorter  170 , event recognizer  180 , and event handler  190 . Event monitor  171  in event sorter  170  detects a contact on touch-sensitive display  112 , and event dispatcher module  174  delivers the event information to application  136 - 1 . A respective event recognizer  180  of application  136 - 1  compares the event information to respective event definitions  186 , and determines whether a first contact at a first location on the touch-sensitive surface (or whether rotation of the device) corresponds to a predefined event or sub-event, such as selection of an object on a user interface, or rotation of the device from one orientation to another. When a respective predefined event or sub-event is detected, event recognizer  180  activates an event handler  190  associated with the detection of the event or sub-event. Event handler  190  optionally uses or calls data updater  176  or object updater  177  to update the application internal state  192 . In some embodiments, event handler  190  accesses a respective GUI updater  178  to update what is displayed by the application. Similarly, it would be clear to a person having ordinary skill in the art how other processes can be implemented based on the components depicted in  FIGS. 1A-1B . 
     In accordance with some embodiments,  FIG. 12  shows a functional block diagram of an electronic device  700  configured in accordance with the principles of the various described embodiments. The functional blocks of the device are, optionally, implemented by hardware, software, or a combination of hardware and software to carry out the principles of the various described embodiments. It is understood by persons of skill in the art that the functional blocks described in  FIG. 12  are, optionally, combined or separated into sub-blocks to implement the principles of the various described embodiments. Therefore, the description herein optionally supports any possible combination or separation or further definition of the functional blocks described herein. 
     As shown in  FIG. 12 , an electronic device  1200  includes a display unit  1202  configured to display a user interface, a touch-sensitive surface unit  1204  configured to receive contacts, one or more sensor units  1206  configured to detect intensity of contacts with the touch-sensitive surface unit  1204 ; and a processing unit  1208  coupled with the display unit  1202 , the touch-sensitive surface unit  1204  and the one or more sensor units  1206 . In some embodiments, the processing unit  1208  includes: a presenting unit  1210 , a detecting unit  1212 , a scrolling unit  1214 , a moving unit  1216 , a display enabling unit  1218 , a changing unit  1220 , an accelerating unit  1222 , a restoring unit  1224 , an inserting unit  1226 , a generating unit  1228 , and an applying unit  1230 . 
     The processing unit  1208  is configured to: present (e.g., with the presenting unit  1210 ) a first portion of a list of items on the display unit; detect (e.g., with the detecting unit  1212 ) a contact on the touch-sensitive surface unit while the first portion of the list of items is presented on the display unit; detect (e.g., with the detecting unit  1212 ) a first movement of the contact on the touch-sensitive surface unit while a characteristic intensity of the contact remains below a first intensity threshold; in response to detecting the first movement of the contact on the touch-sensitive surface unit while the characteristic intensity of the contact remains below the first intensity threshold, scroll (e.g., with the scrolling unit  1214 ) the list of items to present a second portion of the list of items on the display unit in accordance with the first movement of the contact on the touch-sensitive surface unit; while a focus selector associated with the contact is located on a first item in the second portion of the list of items presented on the display unit, detect (e.g., with the detecting unit  1212 ) an increase in the characteristic intensity of the contact above the first intensity threshold followed by a second movement of the contact on the touch-sensitive surface unit; and, in response to detecting the increase in the characteristic intensity of the contact above the first intensity threshold followed by the second movement of the contact on the touch-sensitive surface unit, move (e.g., with the moving unit  1216 ) the first item relative to other items in the second portion of the list of items presented on the display unit in accordance with the second movement of the contact. 
     In some embodiments, the processing unit is configured to: in response to detecting the increase in the characteristic intensity of the contact above the first intensity threshold followed by the second movement of the contact on the touch-sensitive surface unit, while the focus selector associated with the contact is located on the first item in the second portion of the list of items, change (e.g., with the changing unit  1220 ) an appearance of the first item. 
     In some embodiments, changing the appearance of the first item includes dynamically changing a size of the first item in accordance with the characteristic intensity of the contact. 
     In some embodiments, the processing unit is configured to: in accordance with the second movement of the contact on the touch-sensitive surface unit, move (e.g., with the moving unit  1216 ) the first item by a first distance relative to a second item that is adjacent to the first item to at least partially reveal a first item slot associated with the first item on the display unit. 
     In some embodiments, moving the first item by the first distance relative to the second item that is adjacent to the first item includes: during an initial portion of the second movement of the contact, move (e.g., with the moving unit  1216 ) the first item at a slower speed than the focus selector to create a distance lag between the first item and the focus selector; and during a subsequent portion of the second movement of the contact following the initial portion of the second movement of the contact, accelerate (e.g., with the accelerating unit  1222 ) the movement of the first item to eliminate the distance lag between the first item and the focus selector. 
     In some embodiments, the processing unit is configured to: detect (e.g., with the detecting unit  1212 ) a lift-off of the contact upon moving the first item by the first distance relative to the second item that is adjacent to the first item; and, in accordance with a determination that the first distance is smaller than a first threshold distance, restore (e.g., with the restoring unit  1224 ) the first item into the first item slot associated with the first item on the display unit. 
     In some embodiments, the processing unit is configured to: in accordance with a determination that the first distance is greater than a first threshold distance, move (e.g., with the moving unit  1216 ) the second item into the first item slot associated with the first item to reveal a second item slot associated with the second item. 
     In some embodiments, the processing unit is configured to: detect (e.g., with the detecting unit  1212 ) a lift-off of the contact while the second item slot associated with the second item is revealed on the display unit; and in response to detecting the lift-off of the contact while the second item slot associated with the second item is revealed on the display unit, insert (e.g., with the inserting unit  1226 ) the first item into the second item slot. 
     In some embodiments, the processing unit is configured to: during the second movement of the contact, for a plurality of other items besides the first item in the list of items, move (e.g., with the moving unit  1216 ) a respective other item to a respective new item slot and revealing a respective previous item slot for the respective other item on the display unit. 
     In some embodiments, the processing unit is configured to: generate (e.g., with the generating unit  1228 ) a respective tactile output as the respective other item moves to the respective new item slot and reveals the respective previous item slot. 
     In some embodiments, a respective movement of the respective other item changes in accordance with the characteristic intensity of the contact during the second movement of the contact. 
     In some embodiments, the processing unit is configured to: detect (e.g., with the detecting unit  1212 ) that the first item has moved within a second threshold distance of a first end of the displayed second portion of the list of items in accordance with the second movement of the contact; and, in response to detecting that the first item has moved within the second threshold distance of the first end of the displayed second portion of the list of items, scroll (e.g., with the scrolling unit  1214 ) the list of items toward a second end of the displayed second portion of the list of items opposite the first end to enable display (e.g., with the display enabling unit  1218 ) a third portion of the list of items. 
     In some embodiments, scrolling the list of items toward the second end of the displayed second portion of the list of items opposite the first end to enable display the third portion of the list of items includes: dynamically changing (e.g., with the changing unit  1220 ) a scrolling speed of the scrolling toward the second end of the displayed second portion of the list of items in accordance with the characteristic intensity of the contact. 
     In some embodiments, the processing unit is configured to: apply (e.g., with the applying unit  1230 ) a transparency effect to the first item while the first item overlaps with another item in the list of items. 
     The operations in the information processing methods described above are, optionally implemented by running one or more functional modules in information processing apparatus such as general purpose processors (e.g., as described above with respect to  FIGS. 1A and 3 ) or application specific chips. 
     The operations described above with reference to  FIGS. 7A-7C  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 12 . For example, detection operations  704 ,  706 , and  710 ; scrolling operation  708 ; and moving operation  712  are, optionally, implemented by event sorter  170 , event recognizer  180 , and event handler  190 . Event monitor  171  in event sorter  170  detects a contact on touch-sensitive display  112 , and event dispatcher module  174  delivers the event information to application  136 - 1 . A respective event recognizer  180  of application  136 - 1  compares the event information to respective event definitions  186 , and determines whether a first contact at a first location on the touch-sensitive surface (or whether rotation of the device) corresponds to a predefined event or sub-event, such as selection of an object on a user interface, or rotation of the device from one orientation to another. When a respective predefined event or sub-event is detected, event recognizer  180  activates an event handler  190  associated with the detection of the event or sub-event. Event handler  190  optionally uses or calls data updater  176  or object updater  177  to update the application internal state  192 . In some embodiments, event handler  190  accesses a respective GUI updater  178  to update what is displayed by the application. Similarly, it would be clear to a person having ordinary skill in the art how other processes can be implemented based on the components depicted in  FIGS. 1A-1B . 
     In accordance with some embodiments,  FIG. 13  shows a functional block diagram of an electronic device  1300  configured in accordance with the principles of the various described embodiments. The functional blocks of the device are, optionally, implemented by hardware, software, or a combination of hardware and software to carry out the principles of the various described embodiments. It is understood by persons of skill in the art that the functional blocks described in  FIG. 13  are, optionally, combined or separated into sub-blocks to implement the principles of the various described embodiments. Therefore, the description herein optionally supports any possible combination or separation or further definition of the functional blocks described herein. 
     As shown in  FIG. 13 , an electronic device  1300  includes a display unit  1302  configured to display a user interface, a touch-sensitive surface unit  1304  configured to receive contacts, one or more sensor units  1306  configured to detect intensity of contacts with the touch-sensitive surface unit  1304 ; and a processing unit  1308  coupled with the display unit  1302 , the touch-sensitive surface unit  1304  and the one or more sensor units  1306 . In some embodiments, the processing unit  1308  includes: a presenting unit  1310 , a detecting unit  1312 , a translating unit  1314 , an applying unit  1316 , a removing unit  1318 , and a ceasing unit  1320 . 
     The processing unit  1308  is configured to: present (e.g., with the presenting unit  1310 ) a first portion of structured content on the display unit, wherein the structured content includes a plurality of sections, and the first portion includes content from a first section of the plurality of sections; detect (e.g., with the detecting unit  1312 ) a first contact on the touch-sensitive surface unit while the first portion of the structured content is presented on the display unit; detect (e.g., with the detecting unit  1312 ) an increase in a characteristic intensity of the first contact on the touch-sensitive surface unit and detect (e.g., with the detecting unit  1312 ) a first movement of the first contact on the touch-sensitive surface unit; and, in response to detecting the increase in the characteristic intensity of the first contact and detecting the first movement of the first contact: in accordance with a determination that the characteristic intensity of the contact increases above a first intensity threshold, translate (e.g., with the translating unit  1314 ) the structured content to enable display of a start of a second section adjacent to the first section of the structured content at a predefined location on the display unit; and in accordance with a determination that the characteristic intensity of the contact does not increase above the first intensity threshold, translate (e.g., with the translating unit  1314 ) the structured content in accordance with a magnitude of the movement of the contact on the touch-sensitive surface unit. 
     In some embodiments, during the translating of the structured content to enable display of the start of the second section adjacent to the first section on the display unit, a focus selector associated with the first contact is on the structured content. 
     In some embodiments, in response to detecting the increase in the characteristic intensity of the first contact and the first movement of the first contact, the processing unit is configured to apply (e.g., with the applying unit  1316 ) a visual effect on the first portion of the structured content on the display unit. 
     In some embodiments, the processing unit is configured to: remove (e.g., with the removing unit  1318 ) the applied visual effect on the first portion of the structured content on the display unit during the translating of the structured content. 
     In some embodiments, the processing unit is configured to: prior to the determination that the characteristic intensity of the first contact has increased above the first intensity threshold: detect (e.g., with the detecting unit  1312 ) an initial increase in the characteristic intensity of the first contact; and, in response to detecting the initial increase in the characteristic intensity of the first contact, concurrently present (e.g., with the presenting unit  1310 ) a scroll bar with the first portion of the structured content on the display unit, wherein the scroll bar includes a scroll position indicator that indicates a respective position of the first portion of the structured content in the structured content; and, in response to the determination that the characteristic intensity of the first contact has increased above the first intensity threshold, present (e.g., with the presenting unit  1310 ) a plurality of section indicators along with the scroll position indicator, wherein a relative ordering of the section indicators to the scroll position indicator corresponds to relative positions of the sections to the first portion of the structured content in the structured content. 
     In some embodiments, presenting the plurality of section indicators with the scroll bar includes: presenting an animation that shows the plurality of section indicators emerging from the scroll position indicator and spreading out along the scroll bar. 
     In some embodiments, the processing unit is configured to: when translating of the structured content to enable display of the start of the second section adjacent to the first section of the structured content, present (e.g., with the presenting unit  1310 ) an animation that shows the scroll position indicator hopping over a respective section indicator in the plurality of section indicators. 
     In some embodiments, the processing unit is configured to: detect (e.g., with the detecting unit  1312 ) a lift-off of the first contact, and, in response to detecting the lift-off of the first contact, cease (e.g., with the ceasing unit  1320 ) to display the scroll bar, the scroll position indicator, and the plurality of section indicators. 
     In some embodiments, the processing unit is configured to: in response to detecting the lift-off of the first contact, present (e.g., with the presenting unit  1310 ) an animation that shows the plurality of section indicators moving into the scroll position indicator before ceasing the display of the scroll position indicator. 
     In some embodiments, the structured content is translated to enable display of the start of the second section adjacent to the first section of the structured content at the predefined location on the display unit in accordance with a determination that the first movement of the first contact exceeds a first threshold distance. 
     In some embodiments, the characteristic intensity of the first contact is below the first intensity threshold after the first movement of the first contact exceeds the first threshold distance. 
     In some embodiments, the sections in the structured content are mapped to a plurality of vertical positions on the display unit, and the first movement of the first contact from a first position of the plurality of positions to a second position of the plurality of positions results in a translation of the structured content from one section of the structured document that corresponds to the first position on the display unit to another section of the structured content that corresponds to the second position on the display unit. 
     The operations in the information processing methods described above are, optionally implemented by running one or more functional modules in information processing apparatus such as general purpose processors (e.g., as described above with respect to  FIGS. 1A and 3 ) or application specific chips. 
     The operations described above with reference to  FIGS. 8A-8C  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 13 . For example, detection operations  804  and  806  and translation operations  808  are, optionally, implemented by event sorter  170 , event recognizer  180 , and event handler  190 . Event monitor  171  in event sorter  170  detects a contact on touch-sensitive display  112 , and event dispatcher module  174  delivers the event information to application  136 - 1 . A respective event recognizer  180  of application  136 - 1  compares the event information to respective event definitions  186 , and determines whether a first contact at a first location on the touch-sensitive surface (or whether rotation of the device) corresponds to a predefined event or sub-event, such as selection of an object on a user interface, or rotation of the device from one orientation to another. When a respective predefined event or sub-event is detected, event recognizer  180  activates an event handler  190  associated with the detection of the event or sub-event. Event handler  190  optionally uses or calls data updater  176  or object updater  177  to update the application internal state  192 . In some embodiments, event handler  190  accesses a respective GUI updater  178  to update what is displayed by the application. Similarly, it would be clear to a person having ordinary skill in the art how other processes can be implemented based on the components depicted in  FIGS. 1A-1B . 
     In accordance with some embodiments,  FIG. 14  shows a functional block diagram of an electronic device  1400  configured in accordance with the principles of the various described embodiments. The functional blocks of the device are, optionally, implemented by hardware, software, or a combination of hardware and software to carry out the principles of the various described embodiments. It is understood by persons of skill in the art that the functional blocks described in  FIG. 14  are, optionally, combined or separated into sub-blocks to implement the principles of the various described embodiments. Therefore, the description herein optionally supports any possible combination or separation or further definition of the functional blocks described herein. 
     As shown in  FIG. 14 , an electronic device  1400  includes a display unit  1402  configured to display a user interface, a touch-sensitive surface unit  1404  configured to receive contacts, one or more sensor units  1406  configured to detect intensity of contacts with the touch-sensitive surface unit  1404 ; and a processing unit  1408  coupled with the display unit  1402 , the touch-sensitive surface unit  1404  and the one or more sensor units  1406 . In some embodiments, the processing unit  1408  includes: a presenting unit  1410 , a detecting unit  1412 , a scrolling unit  1414 , a moving unit  1416 , an applying unit  1418 , a changing unit  1420 , and a performing unit  1422 . 
     The processing unit  1408  is configured to: present (e.g., with the presenting unit  1410 ) a first portion of content on the display unit; while presenting the first portion of the content on the display unit: detect (e.g., with the detecting unit  1412 ) a first contact on the touch-sensitive surface unit; and detect (e.g., with the detecting unit  1412 ) a first movement of the first contact on the touch-sensitive surface unit; in response to detecting the first movement of the first contact, scroll (e.g., with the scrolling unit  1414 ) the content to present a second portion of the content on the display unit in accordance with the first movement of the first contact; detect (e.g., with the detecting unit  1412 ) an increase in intensity of the first contact on the touch-sensitive surface unit during the first movement of the first contact on the touch-sensitive surface unit; after detecting the increase in intensity of the first contact on the touch-sensitive surface unit during the first movement of the first contact on the touch-sensitive surface unit, detect (e.g., with the detecting unit  1412 ) a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit; and, in response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit, move (e.g., with the moving unit  1416 ) the content on the display unit by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact. 
     In some embodiments, the characteristic speed of the first movement is a first speed and moving the content on the display unit by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes: in accordance with a determination that the characteristic intensity is a first intensity, moving (e.g., with the moving unit  1416 ) the content by a first amount; and, in accordance with a determination that the characteristic intensity is a second intensity that is different from the first intensity, moving (e.g., with the moving unit  1416 ) the content by a second amount that is different from the first amount. 
     In some embodiments, the first intensity is greater than the second intensity and the first amount of movement is greater than the second amount of movement. 
     In some embodiments, the first intensity is less than the second intensity and the first amount of movement is greater than the second amount of movement. 
     In some embodiments, moving the content on the display unit by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes setting a simulated friction based on the characteristic intensity of the first contact. 
     In some embodiments, moving the content on the display unit by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes setting a simulated inertia based on the characteristic intensity of the first contact. 
     In some embodiments, moving the content on the display unit by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes setting an initial speed of movement for moving the content based on the characteristic intensity of the first contact. 
     In some embodiments, moving the content on the display unit by an amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact includes: determining an initial speed for continued scrolling after the lift-off of the first contact based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact; and continuing the scrolling of the content after the lift-off of the first contact with the initial speed determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact. 
     In some embodiments, the processing unit is configured to in response to detecting the increase in intensity of the first contact on the touch-sensitive surface unit, dynamically apply (e.g., with the applying unit  1418 ) a visual effect on the first portion of content on the display unit in accordance with a current intensity of the first contact on the touch-sensitive surface unit. 
     In some embodiments, the processing unit is configured to: present (e.g., with the presenting unit  1418 ) a scroll bar on the display unit, wherein the scroll bar includes a scroll position indicator that indicates a respective position of a currently displayed portion of the content in the content; and present (e.g., with the presenting unit  1418 ) a scroll enhancement indicator concurrently with the scroll position indicator, wherein an appearance of the scroll enhancement indicator varies dynamically with a current intensity of the first contact on the touch-sensitive surface unit. 
     In some embodiments, the processing unit is configured to: while moving the content on the display unit by the amount that is determined based on the characteristic intensity of the first contact and the characteristic speed of the first movement detected prior to the lift-off of the first contact, dynamically change (e.g., with the changing unit  1420 ) the appearance of the scroll enhancement indicator in accordance with a current scrolling speed. 
     In some embodiments, moving the content on the display unit by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact includes: applying an intensity filter to an intensity profile of the first contact, wherein the intensity filter shifts the intensity profile by a first time shift past the lift-off of the first contact; and determining an initial speed for moving the content on the display unit after the lift-off of the first contact based on a selected intensity value on the filtered intensity profile. 
     In some embodiments, moving the content on the display unit by an amount that is determined based on a characteristic intensity of the first contact and a characteristic speed of the first movement detected prior to the lift-off of the first contact includes: applying a speed filter to a speed profile of the first contact, wherein the speed filter shifts the speed profile by a second time shift past the lift-off of the first contact; determining an initial speed for moving the content on the display unit after the lift-off of the first contact based on a selected speed value on the shifted speed profile; and moving the content on the display unit with the determined initial speed after the lift-off of the first contact. 
     In some embodiments, the processing unit is configured to: prior to detecting the first movement of the first contact, detect (e.g., with the detecting unit  1412 ) an earlier increase in intensity of the first contact while the first contact remains stationary on the touch-sensitive surface unit. 
     In some embodiments, detecting the earlier increase in intensity of the first contact includes detecting the earlier increase in intensity of the first contact above a first intensity threshold while a focus selector is located on a first user interface element on the display unit, and the processing unit is configured to perform (e.g., with the performing unit  1422 ) a predefined operation associated with the first user interface element in response to detecting the earlier increase in intensity of the first contact above the first intensity threshold while the focus selector is located on the first user interface element on the display unit. 
     The operations in the information processing methods described above are, optionally implemented by running one or more functional modules in information processing apparatus such as general purpose processors (e.g., as described above with respect to  FIGS. 1A and 3 ) or application specific chips. 
     The operations described above with reference to  FIGS. 9A-9D  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 14 . For example, detection operations  904 ,  908 , and  910 , scrolling operation  906 , and moving operation  912  are, optionally, implemented by event sorter  170 , event recognizer  180 , and event handler  190 . Event monitor  171  in event sorter  170  detects a contact on touch-sensitive display  112 , and event dispatcher module  174  delivers the event information to application  136 - 1 . A respective event recognizer  180  of application  136 - 1  compares the event information to respective event definitions  186 , and determines whether a first contact at a first location on the touch-sensitive surface (or whether rotation of the device) corresponds to a predefined event or sub-event, such as selection of an object on a user interface, or rotation of the device from one orientation to another. When a respective predefined event or sub-event is detected, event recognizer  180  activates an event handler  190  associated with the detection of the event or sub-event. Event handler  190  optionally uses or calls data updater  176  or object updater  177  to update the application internal state  192 . In some embodiments, event handler  190  accesses a respective GUI updater  178  to update what is displayed by the application. Similarly, it would be clear to a person having ordinary skill in the art how other processes can be implemented based on the components depicted in  FIGS. 1A-1B . 
     In accordance with some embodiments,  FIG. 15  shows a functional block diagram of an electronic device  1500  configured in accordance with the principles of the various described embodiments. The functional blocks of the device are, optionally, implemented by hardware, software, or a combination of hardware and software to carry out the principles of the various described embodiments. It is understood by persons of skill in the art that the functional blocks described in  FIG. 15  are, optionally, combined or separated into sub-blocks to implement the principles of the various described embodiments. Therefore, the description herein optionally supports any possible combination or separation or further definition of the functional blocks described herein. 
     As shown in  FIG. 15 , an electronic device  1500  includes a display unit  1402  configured to display a user interface, a touch-sensitive surface unit  1504  configured to receive contacts, one or more sensor units  1506  configured to detect intensity of contacts with the touch-sensitive surface unit  1504 ; and a processing unit  1508  coupled with the display unit  1502 , the touch-sensitive surface unit  1504  and the one or more sensor units  1506 . In some embodiments, the processing unit  1508  includes: a presenting unit  1510 , a detecting unit  1512 , scrolling unit  1514 , an applying unit  1516 , a removing unit  1518 , a determining unit  1520 , and a performing unit  1522 . 
     The processing unit  1508  is configured to: present (e.g., with the presenting unit  1510 ); a first portion of content on the display unit; while presenting the first portion of the content: detect (e.g., with the detecting unit  1512 ) a first contact on the touch-sensitive surface unit; and detect (e.g., with the detecting unit  1512 ) a first movement of the first contact on the touch-sensitive surface unit; detect (e.g., with the detecting unit  1512 ) a lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit; and, in response to detecting the lift-off of the first contact following the first movement of the first contact on the touch-sensitive surface unit: in accordance with a determination that the first contact had a characteristic intensity above a respective intensity threshold prior to the lift-off of the first contact, scroll (e.g., with the scrolling unit  1514 ) through the content to a predefined portion of the content; and in accordance with a determination that the first contact had a characteristic intensity below the respective intensity threshold prior to the lift-off of the first contact, scroll (e.g., with the scrolling unit  1514 ) through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement. 
     In some embodiments, scrolling through the content to a predefined portion of the content includes accelerating scrolling of the content to enable display of an end portion of the content on the display unit. 
     In some embodiments, the first movement corresponds to movement toward a top portion of the display unit. 
     In some embodiments, scrolling through the content to a predefined portion of the content includes accelerating scrolling of the content to enable display of a beginning portion of the content on the display unit. 
     In some embodiments, the first movement corresponds to movement toward a bottom portion of the display unit. 
     In some embodiments, scrolling through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement includes: scrolling through the content by a first amount before the lift-off of the first contact; and continuing to scroll through the content by a second amount after the lift-off of the first contact, wherein the scrolling of the content after the lift-off of the first contact is continued at an initial speed that is determined based on the characteristic speed of the first contact during the first movement. 
     In some embodiments, the processing unit is configured to: detect (e.g., with the detecting unit  1512 ) the increase in intensity of the first contact on the touch-sensitive surface unit above the respective intensity threshold during the first movement of the first contact on the touch-sensitive surface unit; and in response to detecting the increase in intensity above the respective intensity threshold, apply (e.g., with the applying unit  1516 ) a visual effect on the first portion of content on the display unit. 
     In some embodiments, the processing unit is configured to remove (e.g., with the removing unit  1518 ) the applied visual effect on the first portion of content on the display unit during the scrolling through the content to the predefined portion of the content. 
     In some embodiments, the processing unit is configured to: apply (e.g., with the applying unit  1516 ) an intensity filter to an intensity profile of the first contact, wherein the intensity filter shifts the intensity profile by a first time shift past the lift-off of the first contact; and determine (e.g., with the determining unit  1520 ) a steady state speed for the scrolling through the content to the predefined portion of the content based on a selected intensity value on the shifted intensity profile. 
     In some embodiments, scrolling through the content by an amount that is determined based on a characteristic speed of the first contact during the first movement includes scrolling through the content to enable display of a second portion of the content, and the processing unit is configured to: while displaying the second portion of the content, detect (e.g., with the detecting unit  1512 ) a predefined input while a focus selector is within a predefined region on the display unit; and in response to detecting the predefined input while the focus selector is within the predefined region on the display unit, scroll (e.g., with the scrolling unit  1514 ) through the content to the predefined portion of the content. 
     In some embodiments, the processing unit is configured to: prior to detecting the first movement of the first contact, detect (e.g., with the detecting unit  1512 ) an earlier increase in intensity of the first contact above the respective intensity threshold while the first contact remains stationary on the touch-sensitive surface unit; and determine (e.g., with the determining unit  1520 ) that the first contact had a characteristic intensity below the respective intensity threshold prior to the lift-off of the first contact in accordance with a determination that the intensity of the first contact remained below the respective intensity threshold during the first movement of the first contact on the touch-sensitive surface unit. 
     In some embodiments, detecting the earlier increase in intensity of the first contact includes detecting the earlier increase in intensity of the first contact above a first intensity threshold while a focus selector is located on a first user interface element on the display unit, and the processing unit is configured to perform (e.g., with the performing unit  1522 ) a predefined operation associated with the first user interface element in response to detecting the earlier increase in intensity of the first contact above the first intensity threshold while the focus selector is located on a first user interface element on the display unit. 
     The operations in the information processing methods described above are, optionally implemented by running one or more functional modules in information processing apparatus such as general purpose processors (e.g., as described above with respect to  FIGS. 1A and 3 ) or application specific chips. 
     The operations described above with reference to  FIGS. 10A-10C  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 15 . For example, detection operations  1004 ,  1006  and scrolling operations  1008  are, optionally, implemented by event sorter  170 , event recognizer  180 , and event handler  190 . Event monitor  171  in event sorter  170  detects a contact on touch-sensitive display  112 , and event dispatcher module  174  delivers the event information to application  136 - 1 . A respective event recognizer  180  of application  136 - 1  compares the event information to respective event definitions  186 , and determines whether a first contact at a first location on the touch-sensitive surface (or whether rotation of the device) corresponds to a predefined event or sub-event, such as selection of an object on a user interface, or rotation of the device from one orientation to another. When a respective predefined event or sub-event is detected, event recognizer  180  activates an event handler  190  associated with the detection of the event or sub-event. Event handler  190  optionally uses or calls data updater  176  or object updater  177  to update the application internal state  192 . In some embodiments, event handler  190  accesses a respective GUI updater  178  to update what is displayed by the application. Similarly, it would be clear to a person having ordinary skill in the art how other processes can be implemented based on the components depicted in  FIGS. 1A-1B . 
     The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, to thereby enable others skilled in the art to best use the invention and various described embodiments with various modifications as are suited to the particular use contemplated.

Metadata:
Filing Date: 20190314
Publication Date: 20210105
Grant Date: 20210105
Priority Date: 20150810
Inventors: KARUNAMUNI, CHANAKA G.
ALONSO RUIZ, MARCOS
KING, NICHOLAS V.
PRESTON, DANIEL T.
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/0482", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0483", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0482", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0483", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0414", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0485", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04855", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0485", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0488", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04855", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0414", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0488", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0485", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0483", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0482", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 56738244