Patent Publication Number: US-10775994-B2

Title: Device, method, and graphical user interface for moving and dropping a user interface object

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 14/536,291, filed Nov. 7, 2014, which is a continuation of PCT Patent Application Serial No. PCT/US2013/040108, filed on May 8, 2013, entitled “Device, Method, and Graphical User Interface for Moving and Dropping a User Interface Object,” which claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 61/778,414, filed on Mar. 13, 2013, entitled “Device, Method, and Graphical User Interface for Moving and Dropping a User Interface Object;” U.S. Provisional Patent Application No. 61/747,278, filed Dec. 29, 2012, entitled “Device, Method, and Graphical User Interface for Manipulating User Interface Objects with Visual and/or Haptic Feedback;” and U.S. Provisional Patent Application No. 61/688,227, filed May 9, 2012, entitled “Device, Method, and Graphical User Interface for Manipulating User Interface Objects with Visual and/or Haptic Feedback,” which applications are incorporated by reference herein in their entireties. 
     This application is also related to the following: U.S. Provisional Patent Application Ser. No. 61/778,092, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Selecting Object within a Group of Objects;” U.S. Provisional Patent Application Ser. No. 61/778,125, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Navigating User Interface Hierarchies;” U.S. Provisional Patent Application Ser. No. 61/778,156, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Manipulating Framed Graphical Objects;” U.S. Provisional Patent Application Ser. No. 61/778,179, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Scrolling Nested Regions;” U.S. Provisional Patent Application Ser. No. 61/778,171, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Displaying Additional Information in Response to a User Contact;” U.S. Provisional Patent Application Ser. No. 61/778,191, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Displaying User Interface Objects Corresponding to an Application;” U.S. Provisional Patent Application Ser. No. 61/778,211, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Facilitating User Interaction with Controls in a User Interface;” U.S. Provisional Patent Application Ser. No. 61/778,239, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Forgoing Generation of Tactile Output for a Multi-Contact Gesture;” U.S. Provisional Patent Application Ser. No. 61/778,284, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Providing Tactile Feedback for Operations Performed in a User Interface;” U.S. Provisional Patent Application Ser. No. 61/778,287, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Providing Feedback for Changing Activation States of a User Interface Object;” U.S. Provisional Patent Application Ser. No. 61/778,363, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Transitioning between Touch Input to Display Output Relationships;” U.S. Provisional Patent Application Ser. No. 61/778,367, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Moving a User Interface Object Based on an Intensity of a Press Input;” U.S. Provisional Patent Application Ser. No. 61/778,265, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Transitioning between Display States in Response to a Gesture;” U.S. Provisional Patent Application Ser. No. 61/778,373, filed on Mar. 12, 2013, entitled “Device, Method, and Graphical User Interface for Managing Activation of a Control Based on Contact Intensity;” U.S. Provisional Patent Application Ser. No. 61/778,412, filed on Mar. 13, 2013, entitled “Device, Method, and Graphical User Interface for Displaying Content Associated with a Corresponding Affordance;” U.S. Provisional Patent Application Ser. No. 61/778,413, filed on Mar. 13, 2013, entitled “Device, Method, and Graphical User Interface for Selecting User Interface Objects;” U.S. Provisional Patent Application Ser. No. 61/778,416, filed on Mar. 13, 2013, entitled “Device, Method, and Graphical User Interface for Determining Whether to Scroll or Select Content;” and U.S. Provisional Patent Application Ser. No. 61/778,418, filed on Mar. 13, 2013, entitled “Device, Method, and Graphical User Interface for Switching between User Interfaces,” which are incorporated herein by reference in their entireties. 
     This application is also related to the following: U.S. Provisional Patent Application Ser. No. 61/645,033, filed on May 9, 2012, entitled “Adaptive Haptic Feedback for Electronic Devices;” U.S. Provisional Patent Application Ser. No. 61/665,603, filed on Jun. 28, 2012, entitled “Adaptive Haptic Feedback for Electronic Devices;” and U.S. Provisional Patent Application Ser. No. 61/681,098, filed on Aug. 8, 2012, entitled “Adaptive Haptic Feedback for Electronic Devices,” which are incorporated herein by reference 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 that detect inputs for manipulating user interfaces. 
     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 touch pads and touch screen displays. Such surfaces are widely used to manipulate user interface objects on a display. 
     Exemplary manipulations include adjusting the position and/or size of one or more user interface objects or activating buttons or opening files/applications represented by user interface objects, as well as associating metadata with one or more user interface objects or otherwise manipulating user interfaces. 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 perform such manipulations on user interface objects in a file management program (e.g., Finder from Apple Inc. of Cupertino, Calif.), an image management application (e.g., Aperture or iPhoto 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.), a website creation application (e.g., iWeb from Apple Inc. of Cupertino, Calif.), a disk authoring application (e.g., iDVD 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 manipulations are cumbersome and inefficient. In addition, existing 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 manipulating user interfaces. Such methods and interfaces optionally complement or replace conventional methods for manipulating user interfaces. Such methods and interfaces reduce the cognitive burden on 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 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 finger contacts and gestures on the touch-sensitive surface. In some embodiments, the functions optionally include image editing, drawing, presenting, word processing, website creating, disk authoring, spreadsheet making, game playing, telephoning, video conferencing, e-mailing, instant messaging, workout support, digital photographing, digital videoing, web browsing, digital music playing, 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. 
     There is a need for electronic devices with faster, more efficient methods and interfaces for previewing and selecting content items. Such methods and interfaces may complement or replace conventional methods for previewing and selecting content items. Such methods and interfaces reduce the cognitive burden on 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. 
     In accordance with some embodiments, a method is performed at an electronic device with a touch-sensitive surface and a display, where the device includes one or more sensors to detect intensity of contacts with the touch-sensitive surface. The method includes displaying a content field on the display and detecting a contact on the touch-sensitive surface, where the contact corresponds to a focus selector on the display. The method further includes, while continuously detecting the contact on the touch-sensitive surface, detecting a press input that includes an increase in intensity of the contact above a respective intensity threshold while the focus selector is over the content field, and in response to detecting the press input, displaying a content menu that includes representations of a plurality of options that correspond to content items. The method also includes, while continuously detecting the contact on the touch-sensitive surface, and while displaying the content menu, detecting movement of the contact that corresponds to movement of the focus selector over a representation of a first content item in the content menu, and in response to the focus selector being over the representation of the first content item in the content menu, displaying a preview of the first content item in the content field. The method further includes detecting a confirmation input while the focus selector associated with the contact is over the representation of the first content item in the content menu and, in response to detecting the confirmation input, inserting the first content item into the content field. 
     In accordance with some embodiments, an electronic device includes a display unit configured to display a content field, a touch-sensitive surface unit configured to receive user contacts, one or more sensor units configured to detect intensity of contacts with the touch-sensitive surface unit, and a processing unit coupled to the display unit, the touch-sensitive surface unit, and the sensor units. The processing unit is configured to detect a contact on the touch-sensitive surface unit, where the contact corresponds to a focus selector on the display unit and, while continuously detecting the contact on the touch-sensitive surface, detect a press input that includes an increase in intensity of the contact above a respective intensity threshold while the focus selector is over the content field, and in response to detecting the press input, enable display of a content menu that includes representations of a plurality of options that correspond to content items. The processing unit is also configured, while continuously detecting the contact on the touch-sensitive surface, and while displaying the content menu, to detect movement of the contact that corresponds to movement of the focus selector over a representation of a first content item in the content menu, and in response to the focus selector being over the representation of the first content item in the content menu, enable display of a preview of the first content item in the content field. The processing unit is further configured to detect a confirmation input while the focus selector associated with the contact is over the representation of the first content item in the content menu and, in response to detecting the confirmation input, insert the first content item into the content field. 
     Thus, electronic devices with displays, touch-sensitive surfaces and one or more sensors to detect intensity of contacts with the touch-sensitive surface are provided with faster, more efficient methods and interfaces for previewing and selecting content items, thereby increasing the effectiveness, efficiency, and user satisfaction with such devices. Such methods and interfaces may complement or replace conventional methods for previewing and selecting content items. 
     There is a need for electronic devices with faster, more efficient methods and interfaces for moving and dropping a user interface object. Such methods and interfaces may complement or replace conventional methods for moving and dropping a user interface object. Such methods and interfaces reduce the cognitive burden on 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. 
     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: detecting a contact with the touch-sensitive surface, wherein the contact is associated with a focus selector that controls movement of a respective user interface object that is currently selected; and while continuously detecting the contact on the touch-sensitive surface: detecting first movement of the contact across the touch-sensitive surface corresponding to movement of the focus selector toward a respective location; in response to detecting the first movement of the contact across the touch-sensitive surface: moving the focus selector on the display in accordance with the first movement of the contact and moving the respective user interface object in accordance with the movement of the focus selector, and determining an intensity of the contact on the touch-sensitive surface while the focus selector is at the respective location on the display; detecting second movement of the contact across the touch-sensitive surface that corresponds to movement of the focus selector away from the respective location; and in response to detecting the second movement of the contact across the touch-sensitive surface: in accordance with a determination that the contact meets respective intensity criteria, moving the focus selector and the user interface object in accordance with the second movement of the contact across the touch-sensitive surface; and in accordance with a determination that the contact does not meet the respective intensity criteria, moving the focus selector in accordance with the second movement of the contact across the touch-sensitive surface without moving the user interface object. 
     In accordance with some embodiments, an electronic device includes a display unit; a touch-sensitive surface unit configured to receive contacts; one or more sensor units configured to detect intensity of contacts with the touch-sensitive surface unit; and a processing unit coupled to the display unit, the touch-sensitive surface unit, and the sensor units. The processing unit is configured to: detect a contact with the touch-sensitive surface unit, wherein the contact is associated with a focus selector that controls movement of a respective user interface object that is currently selected; and while continuously detecting the contact on the touch-sensitive surface unit: detect first movement of the contact across the touch-sensitive surface unit corresponding to movement of the focus selector toward a respective location; in response to detecting the first movement of the contact across the touch-sensitive surface unit: move the focus selector on the display unit in accordance with the first movement of the contact and move the respective user interface object in accordance with the movement of the focus selector, and determine an intensity of the contact on the touch-sensitive surface unit while the focus selector is at the respective location on the display unit; detect second movement of the contact across the touch-sensitive surface unit that corresponds to movement of the focus selector away from the respective location; and in response to detecting the second movement of the contact across the touch-sensitive surface unit: in accordance with a determination that the contact meets respective intensity criteria, move the focus selector and the user interface object in accordance with the second movement of the contact across the touch-sensitive surface unit; and in accordance with a determination that the contact does not meet the respective intensity criteria, move the focus selector in accordance with the second movement of the contact across the touch-sensitive surface unit without moving the user interface object. 
     Thus, electronic devices with displays, touch-sensitive surfaces, and one or more sensors to detect intensity of contacts with the touch-sensitive surface are provided with faster, more efficient methods and interfaces for moving and dropping a user interface object, thereby increasing the effectiveness, efficiency, and user satisfaction with such devices. Such methods and interfaces may complement or replace conventional methods for moving and dropping a user interface object. 
     There is a need for electronic devices with faster, more efficient methods and interfaces for performing an operation in accordance with a selected mode of operation. Such methods and interfaces may complement or replace conventional methods for performing an operation in accordance with a selected mode of operation. Such methods and interfaces reduce the cognitive burden on 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. 
     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, a user interface for the electronic device; detecting a sequence of inputs on the touch-sensitive surface, where detecting the sequence of inputs includes detecting changes in characteristics of a respective contact that is continuously detected on the touch-sensitive surface during the sequence of inputs, the sequence of inputs includes a first input and a second input, the first input includes detecting an increase in intensity of the respective contact, and the second input includes detecting movement of the respective contact on the touch-sensitive surface. The method further includes, in response to detecting the first input: in accordance with a determination that the first input does not include increasing the intensity of the respective contact above a mode-selection intensity threshold, operating in a first mode of operation during the second input, and in accordance with a determination that the first input includes increasing the intensity of the respective contact above the mode-selection intensity threshold, operating in a second mode of operation, distinct from the first mode of operation, during the second input; and in response to detecting the second input, performing an operation in accordance with the second input based at least in part on whether the device is operating in the first mode of operation or the second mode of operation. 
     In accordance with some embodiments, an electronic device includes a display unit configured to display a user interface for the electronic device, a touch-sensitive surface unit configured to receive inputs, one or more sensors configured to detect intensity of contacts with the touch-sensitive surface unit, and a processing unit coupled to the display unit, the touch-sensitive surface unit, and the sensors. The processing unit is configured to: detect a sequence of inputs on the touch-sensitive surface unit, where detecting the sequence of inputs includes detecting changes in characteristics of a respective contact that is continuously detected on the touch-sensitive surface unit during the sequence of inputs, the sequence of inputs includes a first input and a second input, the first input includes detecting an increase in intensity of the respective contact, and the second input includes detecting movement of the respective contact on the touch-sensitive surface unit. The processing unit is further configured to, in response to detecting the first input: in accordance with a determination that the first input does not include increasing the intensity of the respective contact above a mode-selection intensity threshold, operate in a first mode of operation during the second input, and in accordance with a determination that the first input includes increasing the intensity of the respective contact above the mode-selection intensity threshold, operate in a second mode of operation, distinct from the first mode of operation, during the second input; and in response to detecting the second input, perform an operation in accordance with the second input based at least in part on whether the device is operating in the first mode of operation or the second mode of operation. 
     Thus, electronic devices with displays, touch-sensitive surfaces, and one or more sensors to detect intensity of contacts with the touch-sensitive surface are provided with faster, more efficient methods and interfaces for performing an operation in accordance with a selected mode of operation, thereby increasing the effectiveness, efficiency, and user satisfaction with such devices. Such methods and interfaces may complement or replace conventional methods for performing an operation in accordance with a selected mode of operation. 
     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 the operations of any of the methods referred to in the fifth paragraph of the Description of Embodiments. 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 referred to in the fifth paragraph of the Description of Embodiments, which are updated in response to inputs, as described in any of the methods referred to in the fifth paragraph of the Description of Embodiments. 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 the operations of any of the methods referred to in the fifth paragraph of the Description of Embodiments. 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 the operations of any of the methods referred to in the fifth paragraph of the Description of Embodiments. In accordance with some embodiments, an information processing apparatus, for use in an electronic device with a display and a touch-sensitive surface, optionally one or more sensors to detect intensity of contacts with the touch-sensitive surface, includes means for performing the operations of any of the methods referred to in the fifth paragraph of the Description of Embodiments. 
    
    
     
       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. 5A-5N  illustrate exemplary user interfaces for previewing and selecting content items in accordance with some embodiments. 
         FIGS. 6A-6C  are flow diagrams illustrating a method of previewing and selecting content items in accordance with some embodiments. 
         FIG. 7  is a functional block diagram of an electronic device in accordance with some embodiments. 
         FIGS. 8A-8J  illustrate exemplary user interfaces for moving and dropping a user interface object in accordance with some embodiments. 
         FIGS. 9A-9C  are flow diagrams illustrating a method of moving and dropping a user interface object in accordance with some embodiments. 
         FIG. 10  is a functional block diagram of an electronic device in accordance with some embodiments. 
         FIGS. 11A-11W  illustrate exemplary user interfaces for performing an operation in accordance with a selected mode of operation in accordance with some embodiments. 
         FIGS. 12A-12D  are flow diagrams illustrating a method of performing an operation in accordance with a selected mode of operation in accordance with some embodiments. 
         FIG. 13  is a functional block diagram of an electronic device in accordance with some embodiments. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     The methods, devices and GUIs described herein provide visual and/or haptic feedback that makes manipulation of user interface objects more efficient and intuitive for a user. For example, in a system where the clicking action of a trackpad is decoupled from the contact intensity (e.g., contact force, contact pressure, or a substitute therefore) that is needed to reach an activation threshold, the device can generate different tactile outputs (e.g., “different clicks”) for different activation events (e.g., so that clicks that accomplish a particular result are differentiated from clicks that do not produce any result or that accomplish a different result from the particular result). Additionally, tactile outputs can be generated in response to other events that are not related to increasing intensity of a contact, such as generating a tactile output (e.g., a “detent”) when a user interface object is moved to a particular position, boundary or orientation, or when an event occurs at the device. 
     Additionally, in a system where a trackpad or touch-screen display is sensitive to a range of contact intensity that includes more than one or two specific intensity values (e.g., more than a simple on/off, binary intensity determination), the user interface can provide responses (e.g., visual or tactile cues) that are indicative of the intensity of the contact within the range. In some implementations, a pre-activation-threshold response and/or a post-activation-threshold response to an input are displayed as continuous animations. As one example of such a response, a preview of an operation is displayed in response to detecting an increase in contact intensity that is still below an activation threshold for performing the operation. As another example of such a response, an animation associated with an operation continues even after the activation threshold for the operation has been reached. Both of these examples provide a user with a continuous response to the force or pressure of a user&#39;s contact, which provides a user with visual and/or haptic feedback that is richer and more intuitive. More specifically, such continuous force responses give the user the experience of being able to press lightly to preview an operation and/or press deeply to push “past” or “through” a predefined user interface state corresponding to the operation. 
     Additionally, for a device with a touch-sensitive surface that is sensitive to a range of contact intensity, multiple contact intensity thresholds can be monitored by the device and different functions can be mapped to different contact intensity thresholds. This serves to increase the available “gesture space” providing easy access to advanced features for users who know that increasing the intensity of a contact at or beyond a second “deep press” intensity threshold will cause the device to perform a different operation from an operation that would be performed if the intensity of the contact is between a first “activation” intensity threshold and the second “deep press” intensity threshold. An advantage of assigning additional functionality to a second “deep press” intensity threshold while maintaining familiar functionality at a first “activation” intensity threshold is that inexperienced users who are, in some circumstances, confused by the additional functionality can use the familiar functionality by just applying an intensity up to the first “activation” intensity threshold, whereas more experienced users can take advantage of the additional functionality by applying an intensity at the second “deep press” intensity threshold. 
     Additionally, for a device with a touch-sensitive surface that is sensitive to a range of contact intensity, the device can provide additional functionality by allowing users to perform complex operations with a single continuous contact. For example, when selecting a group of objects, a user can move a continuous contact around the touch-sensitive surface and can press while dragging (e.g., applying an intensity greater than a “deep press” intensity threshold) to add additional elements to a selection. In this way, a user can intuitively interact with a user interface where pressing harder with a contact causes objects in the user interface to be “stickier.” 
     A number of different approaches to providing an intuitive user interface on a device where a clicking action is decoupled from the force that is needed to reach an activation threshold and/or the device is sensitive to a wide range of contact intensities are described below. Using one or more of these approaches (optionally in conjunction with each other) helps to provide a user interface that intuitively provides users with additional information and functionality, thereby reducing the user&#39;s cognitive burden and improving the human-machine interface. Such improvements in the human-machine interface enable users to use the device faster and more efficiently. For battery-operated devices, these improvements conserve power and increase the time between battery charges. For ease of explanation, systems, methods and user interfaces for including illustrative examples of some of these approaches are described below, as follows:
         Many electronic devices have graphical user interfaces that display content items (e.g., a photo in a photo album). Content items can be customized in various ways, including, for example, selecting, previewing or rearranging photos within a photo album. Such operations often require multiple sequential inputs, which can be time consuming and confusing for users. The embodiments described below provide a convenient and intuitive method of previewing content items and selecting previewed content items in accordance with an intensity of a contact. In particular,  FIGS. 5A-5N  illustrate exemplary user interfaces for previewing and selecting (e.g., in accordance with user inputs on a touch-sensitive surface) content items corresponding to a content field in accordance with some embodiments.  FIGS. 6A-6C  are flow diagrams illustrating a method of previewing and selecting (e.g., in accordance with user inputs on a touch-sensitive surface) content items corresponding to a content field in accordance with some embodiments. The user interfaces in  FIGS. 5A-5N  are further used to illustrate the processes described below with reference to  FIGS. 6A-6C .   Many electronic devices have graphical user interfaces that allow a user to move a user interface object, such as an icon. Sometimes, a user will be required to perform multiple sequential input operations to move a user interface object such as clicking, dragging, and unclicking to drop. This can be time-consuming, confusing, and disruptive to a user&#39;s interaction with the device. The embodiments described below provide a convenient and intuitive method of moving user interface objects and ceasing to move user interface objects based on intensity of a continuously detected contact, thereby providing a more convenient and intuitive user interface for moving user interface objects. In particular,  FIGS. 8A-8J  illustrate exemplary user interfaces for moving and dropping a user interface object.  FIGS. 9A-9C  are flow diagrams illustrating a method of moving and dropping a user interface object. The user interfaces in  FIGS. 8A-8J  are used to illustrate the processes in  FIGS. 9A-9C .   Many electronic devices have user interfaces in which multiple operations are, optionally, performed with a same type of gesture. In some situations, a user can switch between modes of operation by selecting a different mode from a menu of options or making a second contact in addition to the gesture for activating the operation. However, these approaches to switching between modes of operation are inefficient and confusing and can be difficult for users to remember. The embodiments described below provide a convenient and intuitive method of switching between different modes of operation by selecting the mode of operation in accordance with an intensity of an input on a touch-sensitive surface. Below,  FIGS. 11A-11W  illustrate exemplary user interfaces for performing an operation in accordance with a selected mode of operation.  FIGS. 12A-12D  are flow diagrams illustrating a method of performing an operation in accordance with a selected mode of operation. The user interfaces in  FIGS. 11A-11W  are used to illustrate the processes in  FIGS. 12A-12D .       

     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. 
     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 touch pads), 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 touch pad). 
     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 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 displays  112  in accordance with some embodiments. Touch-sensitive display  112  is sometimes called a “touch screen” for convenience, and is sometimes known as or called a touch-sensitive display system. Device  100  includes memory  102  (which optionally includes one or more computer readable storage mediums), memory controller  122 , one or more processing units (CPU&#39;s)  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 “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) 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) 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). 
     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, or a combination of both hardware and software, 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  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  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  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 802.11b, IEEE 802.11g and/or IEEE 802.11n), 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 screen  112  and other input control devices  116 , to 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 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 to any (or none) of the following: a keyboard, infrared port, USB port, and 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  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 screen  112 . Touch screen  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. 
     Touch screen  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 screen  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 screen  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 screen  112 . In an exemplary embodiment, a point of contact between touch screen  112  and the user corresponds to a finger of the user. 
     Touch screen  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 screen  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 screen  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 screen  112  optionally has a video resolution in excess of 100 dpi. In some embodiments, the touch screen has a video resolution of approximately 160 dpi. The user optionally makes contact with touch screen  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 primarily 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 screen  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 to optical sensor controller  158  in I/O subsystem  106 . Optical sensor  164  optionally includes charge-coupled device (CCD) or complementary metal-oxide semiconductor (CMOS) phototransistors. Optical sensor  164  receives 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  164  optionally captures still images or video. In some embodiments, an optical sensor is located on the back of device  100 , opposite touch screen display  112  on the front of the device, so that the touch screen display 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, optionally, obtained for videoconferencing while the user views the other video conference participants on the touch screen display. 
     Device  100  optionally also includes one or more contact intensity sensors  165 .  FIG. 1A  shows a contact intensity sensor coupled to intensity sensor controller  159  in I/O subsystem  106 . Contact intensity sensor  165  optionally includes 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  165  receives 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  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 to peripherals interface  118 . Alternately, proximity sensor  166  is coupled to input controller  160  in I/O subsystem  106 . In some embodiments, the proximity sensor turns off and disables touch screen  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 to haptic feedback controller  161  in I/O subsystem  106 . Tactile output generator  167  optionally includes 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). Contact intensity sensor  165  receives 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 screen display  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 to peripherals interface  118 . Alternately, accelerometer  168  is, optionally, coupled to 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 , 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 screen display  112 ; sensor state, including information obtained from the device&#39;s various sensors and input control devices  116 ; and location information concerning the device&#39;s location and/or attitude. 
     Operating system  126  (e.g., 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 on iPod (trademark of Apple Inc.) devices. 
     Contact/motion module  130  optionally detects contact with touch screen  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, 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 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. 
     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). 
     Contact/motion module  130  optionally detects a gesture input by a user. Different gestures on the touch-sensitive surface have different contact patterns and intensities. 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. 
     Graphics module  132  includes various known software components for rendering and displaying graphics on touch screen  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 screen  112 , display controller  156 , contact module  130 , graphics module  132 , and text input module  134 , contacts module  137  are, optionally, used 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 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 screen  112 , display controller  156 , contact module  130 , graphics module  132 , and text input module  134 , telephone module  138  are, optionally, used 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 screen  112 , display controller  156 , optical sensor  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 screen  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 screen  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, 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, or IMPS). 
     In conjunction with RF circuitry  108 , touch screen  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 (sports devices); 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 screen  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, or delete a still image or video from memory  102 . 
     In conjunction with touch screen  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 screen  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 screen  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 screen  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 screen  112 , display system controller  156 , contact module  130 , graphics module  132 , text input module  134 , and browser module  147 , the widget creator module  150  are, optionally, used by a user to create widgets (e.g., turning a user-specified portion of a web page into a widget). 
     In conjunction with touch screen  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 screen  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 screen  112  or on an external, connected display 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 screen  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 screen  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  are, optionally, used 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 screen  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 instructions that allow the user to access, browse, receive (e.g., by streaming and/or download), play back (e.g., on the touch screen or on an external, connected display 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  137 - 151 ,  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  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  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  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  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  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  112 , when a touch is detected on touch-sensitive display  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  112  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 touch screen  112 . 
     In one embodiment, device  100  includes touch screen  112 , 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 an alternative embodiment, 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 screen  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 (CPU&#39;s)  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 is, 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 “Text;”   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, icon  422  for video and music player module  152  are 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  (e.g., touch screen display  112 ). 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 . 
     Although some of the examples which 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), 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 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 touch screen  112  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). 
     The user interface figures described below 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 , and/or one or more other intensity thresholds). 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 an 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. 
     An increase of 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 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 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 intensity of the contact from an intensity above the contact-detection intensity threshold IT 0  to an intensity below the contact 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., 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., 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., 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 either: 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, and/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. 
     User Interfaces and Associated Processes 
     Previewing and Selecting Content Items 
     Many electronic devices have graphical user interfaces that include various content fields and a multitude of content items. For example, photo album software allows a user to arrange and customize pictures to be displayed or printed at a later time. In this example, customizing the pictures optionally includes selecting between various pictures to display in a particular frame. Some methods of selecting between various pictures require multiple sequential inputs performed with different contacts to navigate through pop-up or drop-down menus, which can take a long time and be confusing to a user. There is a need to provide a fast, efficient, and convenient way for previewing and selecting content items corresponding to a content field that reduce or eliminate separate steps or inputs or user interfaces that a user would otherwise navigate through to perform a content selection operation. The embodiments below improve on the existing methods by reducing the cognitive burden on a user and produce a more efficient human-machine interface. 
       FIGS. 5A-5N  illustrate exemplary user interfaces for previewing and selecting content items corresponding to a content field 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-6C .  FIGS. 5A-5L  include intensity diagrams that show the current intensity of the contact on the touch-sensitive surface relative to a plurality of intensity thresholds including a respective threshold (e.g., “IT L ”). In some embodiments, operations similar to those described below with reference to IT L  are performed with reference to a different intensity threshold (e.g., “IT D ”). 
       FIGS. 5A-5F  illustrate an example of previewing and selecting electronic messages corresponding to a reading pane.  FIGS. 5A-5F  show user interface  18002  including email application  18004  with reading pane  18006  displayed on display  450  of a device (e.g., device  300 ,  FIG. 3 ).  FIGS. 5A-5F  also show contact  18010  on touch-sensitive surface  451  and intensity of contact  18010 . In accordance with some embodiments,  FIGS. 5A-5F  further illustrate a displayed representation of focus selector (e.g., cursor  18008 ).  FIG. 5B  shows intensity of contact  18010  above IT L  while cursor  18008  is over reading pane  18006 .  FIG. 5B  also shows content menu  18012  including multiple options that correspond to individual emails.  FIG. 5C  shows movement of contact  18010  and corresponding movement of cursor  18008  to a position over a representation of email  1  in content menu  18012 .  FIG. 5D  shows cursor  18008  over the representation of email  1  in content menu  18012  and email  1  preview  18014  displayed in reading pane  18006 .  FIGS. 5D-5E  shows intensity of contact  18010  increasing from an intensity below IT D  in  FIG. 5D  to an intensity above IT D  in  FIG. 5E  while cursor  18008  is over the representation of email  1  in content menu  18012 .  FIG. 5E  also shows email  1  preview  18014  expanding in reading pane  18006 .  FIG. 5F  shows email  18016  in reading pane  18006 . In some embodiments, the email is inserted into reading pane  18006  when the intensity of contact  18010  increases above IT D . In some embodiments, the email is inserted into reading pane  18006  when, after the intensity of contact  18010  reached an intensity above IT D , the intensity of contact  18010  is reduced below a hysteresis intensity threshold associated with (and below) IT D . 
     In some embodiments, the device is an electronic device with a separate display (e.g., display  450 ) and a separate touch-sensitive surface (e.g., touch-sensitive surface  451 ). In some embodiments, the device is portable multifunction device  100 , the display is touch-sensitive display system  112 , and the touch-sensitive surface includes contact intensity sensors  165  on the display ( FIG. 1A ). For convenience of explanation, the embodiments described with reference to  FIGS. 5A-5F  will be discussed with reference to display  450  and a separate touch-sensitive surface  451 . However, analogous operations are, optionally, performed on a device with a touch-sensitive display system  112  in response to detecting the contacts described in  FIGS. 5A-5F  on the touch-sensitive display system  112  while displaying the user interfaces shown in  FIGS. 5A-5F  on the touch-sensitive display system  112 ; in such embodiments, the focus selector is, optionally: a respective contact, a representative point corresponding to a 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 , in place of cursor  18008 . 
       FIGS. 5G-5N  illustrate an example of previewing and selecting pictures corresponding to a picture frame.  FIGS. 5G-5N  show touch screen  112  on portable multifunction device  100 .  FIGS. 5G-5N  further show picture editing application  18020  including frame  18022  displayed on touch screen  112 .  FIG. 5G  shows contact  18024  with intensity below IT L  detected over frame  18022 .  FIGS. 5G-5H  show an intensity of contact  18024  increasing from an intensity below IT L  in  FIG. 5G  to an intensity above IT L  in  FIG. 5H  and content menu  18026  including picture representations  18028  being displayed in response to detecting the increase in intensity of contact  18024 .  FIGS. 51-5J  show movement of contact  18024  over picture representation  18028 - 2  in content menu  18026 .  FIG. 5J  shows contact  18024  over picture representation  18028 - 2  and picture  2  preview  18030  in frame  18022 .  FIGS. 5K-5L  shows movement of contact  18024  over picture representation  18028 - 1  in content menu  18026 .  FIG. 5L  shows contact  18024  over picture representation  18028 - 1  and picture  1  preview  18032  in frame  18022 .  FIG. 5M  shows liftoff of contact  18024  (e.g., a decrease in intensity of contact  18024  from an intensity above IT 0  to an intensity below IT 0 ) while over picture representation  18028 - 1 .  FIG. 5M  also shows picture  1  preview  18032  expanding in frame  18022 .  FIG. 5N  shows picture  18034  in frame  18022 . 
       FIGS. 6A-6C  are flow diagrams illustrating method  18100  of previewing and selecting content items corresponding to a content field in accordance with some embodiments. Method  18100  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display and a touch-sensitive surface. In some embodiments, the display is a touch screen display and the touch-sensitive surface is on the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  18100  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, method  18100  provides an intuitive way to preview and select content items corresponding to a content field in accordance with some embodiments. The method reduces the cognitive burden on a user when navigating user interface hierarchies, thereby creating a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to previewing and selecting content items faster and more efficiently conserves power and increases the time between battery charges. 
     The device displays ( 18102 ) a content field (e.g., a frame for an image or picture, a text box, or a field for entering a numerical value) on the display. For example, the device in  FIG. 5A  displays reading pane  18006  in email application  18004 . As another example, the device in  FIG. 5G  displays a frame  18022  in a picture editing application  18020 . 
     The device detects ( 18104 ) a contact on the touch-sensitive surface, where the contact corresponds to a focus selector on the display. For example, the device in  FIG. 5A  detects contact  18010  on touch-sensitive surface  451  corresponding to cursor  18008  on display  450 . As another example, the device in  FIG. 5G  detects a contact  18024  on touch screen  112 . 
     While continuously detecting ( 18106 ) the contact on the touch-sensitive surface: the device detects ( 18108 ) a press input that includes an increase in intensity of the contact above a respective intensity threshold (e.g., IT L ) while the focus selector is over the content field. In some embodiments, the respective intensity threshold is an intensity threshold that is higher than an input-detection intensity threshold at which the contact is initially detected. For example, in  FIGS. 5A-5B  the device detects the intensity of contact  18010  increasing above IT L  while cursor  18008  is over reading pane  18006 . As another example, in  FIGS. 5G-5H , the device detects the intensity of contact  18024  increasing from an intensity below IT L  to an intensity above IT L . 
     In response to detecting the press input, the device displays ( 18110 ) a content menu that includes representations of a plurality of options that correspond to content items. For example, the device in  FIG. 5B  displays content menu  18012  including a multitude of email representations. As another example, in  FIG. 5H , the device displays content menu  18026  including a plurality of picture representations  18028 . 
     While displaying the content menu, the device detects ( 18112 ) movement of the contact that corresponds to movement of the focus selector over a representation of a first content item in the content menu. For example, the device in  FIGS. 5C-5D  detects movement of contact  18010  over the representation of email  1  in content menu  18012 . As another example, in  FIGS. 51-5L , the device detects movement of contact  18024  over picture  1  representation  18028 - 1 . 
     In response to the focus selector being over the representation of the first content item in the content menu, the device displays ( 18114 ) a preview (e.g., a transient preview) of the first content item in the content field. For example,  FIG. 5D  shows cursor  18008  over email  1  representation in content menu  18012  and the device in  FIG. 5D  displays email  1  preview  18014  in reading pane  18006 . As another example, in  FIG. 5L , the device displays picture  1  preview  18032  in frame  18022 . 
     In some embodiments, while continuously detecting the contact, after detecting the first press input and before detecting movement of the contact that corresponds to movement of the focus selector over the representation of the first content item in the content menu: the device detects ( 18116 ) movement of the contact that corresponds to movement of the focus selector over one or more other representations of corresponding other content items besides the first content item and, in response to detecting movement of the contact that corresponds to movement of the focus selector over a representation of one of the other content items, the device displays a preview (e.g., a transient preview) of the corresponding other content item in the content field (e.g., without permanently inserting the other content item in the content field). For example, portable multifunction device  100  in  FIGS. 51-5J  detects movement of contact  18024  over picture representation  18028 - 2  in content menu  18026  and (in  FIG. 5J ) displays picture  2  preview  18030  in frame  18022  (in  FIG. 5J ). In accordance with these embodiments, portable multifunction device  100  detects movement of contact  18024  over picture representation  18028 - 2  in  FIGS. 51-5J  before detecting movement of contact  18024  over picture representation  18028 - 1  in  FIGS. 5K-5L . 
     The device detects ( 18118 ) a confirmation input while the focus selector associated with the contact is over the representation of the first content item in the content menu. For example, the device in  FIGS. 5D-5E  detects an increase in intensity of contact  18010  from an intensity below IT D  in  FIG. 5D  to an intensity above IT D  in  FIG. 5E  while cursor  18008  is over the email  1  representation in content menu  18012 . As another example, in  FIGS. 5L-5M , the device detects a liftoff of contact  18024  from touch screen  112 . 
     In some embodiments, the press input, the movement of the contact, and the confirmation input are performed ( 18120 ) with a single continuous contact (e.g., as part of a single gesture). In accordance with these embodiments, for example, the device in  FIGS. 5A-5F  detects an increase in intensity of contact  18010  above IT L  in  FIG. 5B , movement of contact  18010  in  FIG. 5C , and an increase in intensity of contact  18010  above IT D  in  FIG. 5E  as part of a single, continuous contact (e.g., a single gesture). As another example, contact  18024  is continuously detected throughout  FIGS. 5G-5L . 
     In some embodiments, detecting the confirmation input includes ( 18122 ) detecting liftoff of the contact from the touch-sensitive surface. For example, portable multifunction device  100  in  FIGS. 5L-5M  detects liftoff of contact  18024  and, in response, in  FIG. 5N  inserts picture  18034  in frame  18022 . 
     In some embodiments, detecting the confirmation input includes ( 18124 ) detecting an increase in intensity of the contact above an insertion intensity threshold (e.g., the respective intensity threshold or an intensity threshold above the respective intensity threshold) while the focus selector is over the representation of the first content item in the content menu. For example, the device in  FIGS. 5D-5E  detects an increase in intensity of contact  18010  from an intensity below IT D  in  FIG. 5D  to an intensity above IT D  in  FIG. 5E  and, in response, in  FIG. 5F  inserts email  18016  in reading pane  18006 . 
     In response to detecting the confirmation input, the device inserts ( 18126 ) the first content item into the content field. For example, the device in  FIG. 5N  inserts picture  18034  in frame  18022 . As another example, in  FIG. 5F , the device inserts email  1  into reading pane  18006 . In some implementations, inserting the first content item into the content field enables further operations to be performed on the first content item, including at least one operation not available for use with the corresponding preview. In some implementations, a preview is transient and either not operative or less fully operative compared with the respective content item inserted in the content field. In some implementations, inserting the first content item into the content field means non-transiently associating the first content item with the content field and displaying a representation of the first content item in the content field. For example, in accordance with some implementations, a photo application displays a preview of a photo only when the focus selector is over a corresponding photo representation in a content menu. In this example, if no confirmation input is detected, then the photo preview does not continue when the focus selector stops focusing on the corresponding photo representation in the content menu (e.g., when a cursor or contact moves away from a region corresponding to a representation of the content such as a photo preview). Conversely, in this example, if a confirmation input is detected, then the photo is associated with the photo application and will continue to display after the focus selector stops focusing on the corresponding photo representation in the content menu (e.g., when the cursor or contact moves away from the region corresponding to the representation of the content such as a photo preview). Optionally, in this example, additional photo editing options are available to the user after a confirmation input is detected. 
     In some embodiments, the content items are images and the content field is ( 18128 ) an image frame in an electronic document editing application. For example, in accordance with these embodiments,  FIGS. 5G-5N  show picture editing application  18020  including frame  18022  and content menu  18026  includes picture representations  18028 .  FIG. 5N  further shows picture  18034  in frame  18022 . In some embodiments, the content items are electronic messages and the content field is ( 18130 ) a reading pane in an electronic message application. For example, in accordance with these embodiments,  FIGS. 5A-5F  show email application  18004  including reading pane  18006  and content menu  18012  includes email representations.  FIG. 5F  further shows email  18016  in reading pane  18006 . 
     It should be understood that the particular order in which the operations in  FIGS. 6A-6C  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., those listed in the fifth paragraph of the Description of Embodiments) are also applicable in an analogous manner to method  18100  described above with respect to  FIGS. 6A-6C . For example, the contacts, gestures, intensity thresholds, focus selectors, content fields, content menus, and content items described above with reference to method  18100  optionally have one or more of the characteristics of the contacts, gestures, intensity thresholds, focus selectors, content fields, content menus, and content items described herein with reference to other methods described herein (e.g., those listed in the fifth paragraph of the Description of Embodiments). For brevity, these details are not repeated here. 
     In accordance with some embodiments,  FIG. 7  shows a functional block diagram of an electronic device  18200  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. 7  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. 7 , electronic device  18200  includes display unit  18202  configured to display a content field, touch-sensitive surface unit  18204  configured to receive user contacts, one or more sensor units  18205  configured to detect intensity of contacts with the touch-sensitive surface unit, and processing unit  18206  coupled to display unit  18202 , touch-sensitive surface unit  18204 , and sensor units  18205 . In some embodiments, processing unit  18206  includes detecting unit  18208 , display enabling unit  18210 , and inserting unit  18212 . 
     Processing unit  18206  is configured to detect (e.g., with detecting unit  18208 ) a contact on touch-sensitive surface unit  18204 , where the contact corresponds to a focus selector on the display unit, and while continuously detecting the contact on touch-sensitive surface unit  18204 , detect (e.g., with detecting unit  18208 ) a press input that includes an increase in intensity of the contact above a respective intensity threshold while the focus selector is over the content field, and in response to detecting the press input, enable display of (e.g., with display enabling unit  18210 ) a content menu that includes representations of a plurality of options that correspond to content items. Processing unit  18206  is also configured, while continuously detecting the contact on touch-sensitive surface unit  18204 , and while displaying the content menu, to detect (e.g., with detecting unit  18208 ) movement of the contact that corresponds to movement of the focus selector over a representation of a first content item in the content menu, and, in response to the focus selector being over the representation of the first content item in the content menu, enable display of (e.g., with display enabling unit  18210 ) a preview of the first content item in the content field. Processing unit  18206  is further configured to detect (e.g., with detecting unit  18208 ) a confirmation input while the focus selector associated with the contact is over the representation of the first content item in the content menu and, in response to detecting the confirmation input, insert (e.g., with inserting unit  18212 ) the first content item into the content field. 
     In some embodiments, the press input, the movement of the contact, and the confirmation input are performed with a single continuous contact. 
     In some embodiments, detecting (e.g., with detecting unit  18208 ) the confirmation input includes detecting liftoff of the contact from touch-sensitive surface unit  18204 . 
     In some embodiments, detecting (e.g., with detecting unit  18208 ) the confirmation input includes detecting an increase in intensity of the contact above an insertion intensity threshold while the focus selector is over the representation of the first content item in the content menu. 
     In some embodiments, processing unit  18206  is further configured to, while continuously detecting the contact, after detecting (e.g., with detecting unit  18208 ) the first press input and before detecting (e.g., with detecting unit  18208 ) movement of the contact that corresponds to movement of the focus selector over the representation of the first content item in the content menu, detect (e.g., with detecting unit  18208 ) movement of the contact that corresponds to movement of the focus selector over one or more other representations of corresponding other content items besides the first content item and, in response to detecting movement of the contact that corresponds to movement of the focus selector over a representation of one of the other content items, enable display of (e.g., with display enabling unit  18210 ) a preview of the corresponding other content item in the content field. 
     In some embodiments, the content items are images and the content field is an image frame in an electronic document editing application. 
     In some embodiments, the content items are electronic messages and the content field is a reading pane in an electronic message application. 
     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-6C  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 7 . For example, detection operations  18104 ,  18108 ,  18112 , and  18118  and inserting operation  18126  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 corresponds to a predefined event or sub-event, such as selection of an object on a user interface. 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 utilizes 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 . 
     Moving and Dropping a User Interface Object 
     Many electronic devices have graphical user interfaces that allow a user to move a user interface object, such as an icon. In some situations, a user moves a user interface object by selecting it (e.g., making an input with a focus selector over the user interface object) and then making a movement input. Some methods for moving a user interface object make the user move both the focus selector and the user interface object to the target location, and then stop there, before the user can move the focus selector to another user interface object. In the embodiments described below, an improved method for moving a user interface object is achieved. When a user interface object is selected with a focus selector, and the focus selector is moved with a moving contact, the user interface object moves along with the focus selector. At some location during the movement, if the intensity of the contact does not meet certain intensity criteria (e.g., the contact intensity goes below an intensity threshold), the user interface object is dropped at the location. If the intensity of the contact meets the intensity criteria, the focus selector and the user interface object continues moving together. Thus, the user can drag and drop a user interface object at a desired location and keep the focus selector moving (e.g., to another user interface object) without stopping. 
       FIGS. 8A-8J  illustrate exemplary user interfaces for moving and dropping a user interface object 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-9C .  FIGS. 8A-8J  include intensity diagrams that show the current intensity of the contact on the touch-sensitive surface relative to a plurality of intensity thresholds including a light press intensity threshold (e.g., “IT L ”) and a maintain-object-selection intensity threshold (e.g., “IT 1 ”). In some embodiments, operations similar to those described below with reference to “IT L ” are performed with reference to a different intensity threshold (e.g., “IT D ”). In some embodiments, the light press intensity threshold (e.g., “IT L ”) is the different from the maintain-object-selection intensity threshold (e.g., “IT 1 ”), as shown in  FIGS. 8A-8J . However, in some embodiments, the light press intensity threshold (e.g., “IT L ”) is the same as the maintain-object-selection intensity threshold (e.g., “IT 1 ”). 
     In some embodiments, the device is an electronic device with a separate display (e.g., display  450 ) and a separate touch-sensitive surface (e.g., touch-sensitive surface  451 ). In some embodiments, the device is portable multifunction device  100 , the display is touch-sensitive display system  112 , and the touch-sensitive surface includes tactile output generators  167  on the display ( FIG. 1A ). For convenience of explanation, the embodiments described with reference to  FIGS. 8A-8J  and  FIGS. 9A-9C  will be discussed with reference to display  450  and a separate touch-sensitive surface  451 , however analogous operations are, optionally, performed on a device with a touch-sensitive display system  112  in response to detecting the contacts described in  FIGS. 8A-8J  on the touch-sensitive display system  112  while displaying the user interfaces shown in  FIGS. 8A-8J  on the touch-sensitive display system  112 ; in such embodiments, the focus selector is, optionally: a respective contact, a representative point corresponding to a 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 , in place of cursor  18310 . 
       FIG. 8A  illustrates media (e.g., video, audio) player user interface  18304  displayed on display  450  (e.g., display  340 , touch screen  112 ) of a device (e.g., device  300 ,  100 ). Media player user interface  18304  is, optionally, a user interface for a media player application (e.g., a standalone application, web-based application). User interface  18304  includes slider  18306  with thumb  18308 . Slider  18306  is, optionally, a playback progress bar or a volume control. 
     Cursor  18310  is also displayed on display  450 . Cursor  18310  is an example of a focus selector. A user is, optionally, enabled to move cursor  18310  across display  450  by making a corresponding input on touch-sensitive surface  451  or another input device (e.g., a mouse). 
     Cursor  18310  is, optionally, used to control movement of thumb  18308  along slider  18306 . In some embodiments, cursor  18310  is associated with control of movement of thumb  18308  when cursor  18310  is positioned over thumb  18308  and a contact (e.g., contact  18312 ) is detected on touch-sensitive surface  451  of the device and contact  18312  has an intensity above the light press intensity threshold. In response to the detection of contact  18312  on touch-sensitive surface  451  while cursor  18310  is located over thumb  18308 , thumb  18308  is selected and ready to be moved, as shown in  FIG. 8B . Thumb  18308  is moved along slider  18306  by moving contact  18312  on touch-sensitive surface  451 , e.g., with movement  18314 , while thumb  18308  is selected, as shown in  FIGS. 8B-8C . 
     Movement of thumb  18308  is constrained to be along a predefined path defined by slider  18306 . The predefined path defined by slider  18306  runs along the length axis of slider  18306 . Thus, thumb  18308  is moved along slider  18306  in accordance with the component of movement  18314  that is parallel to the length axis of slider  18306 . The component of movement  18314  that is perpendicular to the length axis of slider  18306  moves cursor  18310  but does not affect the movement of thumb  18308 . For example, if contact  18312  is moved diagonally, cursor  18310  would move diagonally in accordance with the diagonal movement of contact  18312 , including away from thumb  18308 , but thumb  18308  would continue to move along the length axis of slider  18306  in accordance with the component of the movement of contact  18312  that is parallel to the length axis of slider  18306 . While the examples described with reference to  FIGS. 8A-8J  are described with reference to a user interface object (e.g., thumb  18308 ) that is constrained to a predefined path (e.g., slider  18306 ), in some embodiments, analogous operations are performed with reference to an object (e.g., a shape in a drawing program, an icon on a desktop or the like) that is not constrained to a predefined path. 
     In  FIGS. 8A-8B , the device detects movement  18311  of contact  18312  across the touch-sensitive surface  451  and, in response to detecting the movement, moves  18307  of cursor  18310  to a location over thumb  18308  on display  450 . 
     In  FIGS. 8B-8C , while cursor  18310  is located over thumb  18308 , the device detects an increase in intensity of contact  18312  from an intensity below the light press intensity threshold (e.g., “IT L ”) in  FIG. 8B  to an intensity above the light press intensity threshold (e.g., “IT L ”) in  FIG. 8C . In response to detecting the increase in intensity of contact  18312  shown in  FIGS. 8B-8C , the device selects (or “picks up”) thumb  18308 . In  FIGS. 8C-8D , while thumb  18308  is selected, the device detects movement  18314  of contact  18312  to the right on touch-sensitive surface  451 , and in response to detecting the movement, moves  18316  cursor  18310  and thumb  18308  to the right along the predefined path corresponding to slider  18306 . 
     In  FIGS. 8D-8E , the device continues to detect that the intensity of contact  18312  is maintained over the maintain-object-selection intensity threshold (e.g., “IT 1 ”) and thus, in response to detecting movement  18318  of contact  18312  further to the right on touch-sensitive surface  451 , the device continues to move  18320  cursor  18310  and thumb  18308  to the right along the predefined path corresponding to slider  18306 . In  FIG. 8F , the device detects liftoff of contact  18312  from touch-sensitive surface  451  and thus does not move cursor  18310  or thumb  18308 , as contact  18312  is no longer detected on the touch-sensitive surface. 
     Similarly, in  FIGS. 8B and 8G , while cursor  18310  is located over thumb  18308 , the device detects an increase in intensity of contact  18312  from an intensity below the light press intensity threshold (e.g., “IT L ”) in  FIG. 8B  to an intensity above the light press intensity threshold (e.g., “IT L ”) in  FIG. 8G . In response to detecting the increase in intensity of contact  18312  shown in  FIGS. 8B and 8G , the device selects (or “picks up”) thumb  18308 . In  FIGS. 8G-8H , while thumb  18308  is selected, the device detects movement  18322  of contact  18312  to the right on touch-sensitive surface  451 , and in response to detecting the movement, moves  18324  cursor  18310  and thumb  18308  to the right along the predefined path corresponding to slider  18306 . Note that the movement of cursor  18310  and thumb  18308  in  FIGS. 8G-8H  is analogous to the movement of cursor  18310  and thumb  18308  in  FIGS. 8C-8D . 
     However, in  FIGS. 8H-8I , the device detects a decrease in intensity of contact  18312  from an intensity above the maintain-object-selection intensity threshold (e.g., “IT 1 ”) in  FIG. 8H  to an intensity below the maintain-object-selection intensity threshold (e.g., “IT 1 ”), or an associated hysteresis intensity threshold, in  FIG. 8I . In response to detecting the decrease in intensity of contact  18312  shown in  FIGS. 8H-8I , the device deselects (or “drops”) thumb  18308 . 
     Subsequently, in  FIGS. 8I-8J , in response to detecting movement  18326  of contact  18312  further to the right on touch-sensitive surface  451 , the device continues to move  18328  cursor  18310  to the right on display  450 , however, because the device detected a decrease in intensity of contact  18310  below the maintain-object-selection intensity threshold (e.g., “IT 1 ”) in  FIGS. 8H-8I , the device does not move thumb  18308  along the predefined path corresponding to slider  18306  (e.g., because the thumb  18308  was “dropped”). Thus, in  FIGS. 8G-8J , the user is able to deselect a selected user interface object without lifting contact  18312  off of touch-sensitive surface  451 , which improves the efficiency of the user&#39;s interaction with the device, by reducing the number of liftoff operations that the user has to perform. 
     After the device has deselected (e.g., dropped) thumb  18308 , as shown in  FIGS. 8I-8J , the user is enabled to select a different user interface object by moving cursor  18310  over the different user interface object and increasing the intensity of contact  18312  over the light press intensity threshold (optionally without lifting contact  18312  off of touch-sensitive surface  451 ) while cursor  18310  is over the different user interface object. 
       FIGS. 9A-9C  are flow diagrams illustrating a method  18400  of moving and dropping a user interface object in accordance with some embodiments. The method  18400  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display and a touch-sensitive surface. In some embodiments, the display is a touch screen display and the touch-sensitive surface is on the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  18400  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, the method  18400  provides an intuitive way to move and drop a user interface object. The method reduces the cognitive burden on a user when moving and dropping a user interface object, thereby creating a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to move and drop a user interface object faster and more efficiently conserves power and increases the time between battery charges. 
     The device detects ( 18402 ) a contact (e.g., a finger contact) with the touch-sensitive surface, where the contact is associated with a focus selector (e.g., cursor  18310  or a contact on a touch screen) that controls movement of a respective user interface object that is currently selected. The user interface object is, optionally, a thumb or handle on a slider (e.g., thumb  18308 ) or a free-moving user interface object. For example, in  FIG. 8B , the device detects, on touch-sensitive surface  451 , contact  18312 , which is associated with cursor  18310  that controls movement of selected thumb  18308 . 
     While continuously detecting ( 18404 ) the contact on the touch-sensitive surface, the device detects ( 18406 ) first movement of the contact across the touch-sensitive surface corresponding to movement of the focus selector toward a respective location (e.g., the respective location is a location where the user will attempt to “drop” the object). As shown in  FIGS. 8C-8D , for example, the device detects movement  18314  of contact  18312  across touch-sensitive surface  451 . Similarly, in  FIGS. 8G-8H , the device detects movement  18322  of contact  18312  across touch-sensitive surface  451 . Movement  18314  (or movement  18322 ) corresponds to movement of cursor  18310  toward a respective location (e.g., a target location for dropping thumb  18308 ) on display  450 . 
     In response ( 18408 ) to detecting the first movement of the contact across the touch-sensitive surface, the device moves ( 18410 ) the focus selector on the display in accordance with the first movement of the contact and moves the respective user interface object in accordance with the movement of the focus selector. The device also determines ( 18416 ) an intensity of the contact on the touch-sensitive surface while the focus selector is at the respective location on the display. For example, in response to detecting movement  18314  of contact  18312 , the device moves cursor  18310  with movement  18316  in accordance with movement  18314  of contact  18312 , and moves thumb  18308  in accordance with the movement of the cursor, as shown in  FIG. 8D . The device also determines the intensity of contact  18312  while cursor  18310  is at the target location. In  FIG. 8H , in response to detecting movement  18322  of contact  18312 , the device moves cursor  18310  with movement  18324  in accordance with movement  18322  of contact  18312 , and moves thumb  18308  in accordance with the movement of the cursor. The device also determines the intensity of contact  18312  while cursor  18310  is at the target location. 
     In some embodiments, movement of the respective user interface object is ( 18412 ) constrained to a predefined path in the user interface, and moving the respective user interface object in accordance with movement of the focus selector includes moving the respective user interface object along the predefined path in accordance with a component of motion of the focus selector that corresponds to an allowed direction of motion along the predefined path (e.g., a thumb/handle in a scrubber or slider bar). For example, movement of thumb  18308  is constrained to the path predefined by slider  18306 , and thumb  18308  is moved in accordance with the component of the movement of cursor  18310  that is parallel to the path defined by slider  18306  (e.g., the horizontal component of the movement of cursor  18310 , which is parallel to the length axis of slider  18306 , as depicted in  FIGS. 8B-8C ). 
     In some embodiments, the respective user interface object has ( 18414 ) a two dimensional range of motion, and moving the respective user interface object in accordance with movement of the focus selector includes moving the respective user interface object to a location at or adjacent to the focus selector on the display (e.g., the respective user interface object is a document icon that can be moved laterally on the display in a two dimensional plane and is not constrained to a predefined path such as a scrubber or a slider bar). 
     The device detects ( 18418 ) second movement of the contact across the touch-sensitive surface that corresponds to movement of the focus selector away from the respective location. For example, in  FIGS. 8D-8E , the device detects movement  18318  of contact  18312 , which corresponds to movement of cursor  18310  away from the target location. In  FIGS. 8I-8J , the device detects movement  18326  of contact  18312 , which corresponds to movement of cursor  18310  away from the target location. 
     In response ( 18420 ) to detecting the second movement of the contact across the touch-sensitive surface, in accordance with a determination that the contact meets respective intensity criteria, the device moves ( 18422 ) the focus selector and the user interface object in accordance with the second movement of the contact across the touch-sensitive surface (e.g., detecting an unsuccessful user interface object drop). For example, in  FIGS. 8D-8E , in response to detecting movement  18318  of contact  18312  that meets the intensity criteria (e.g., because the intensity of contact  18312  is above IT 1 ), the device moves cursor  18310  with movement  18318  and moves  18320  thumb  18308  in accordance with movement of cursor  18310 , as thumb  18308  is still selected. In some embodiments, the respective intensity criteria include a respective intensity threshold (e.g., IT 1  or IT L ), and the contact meets the respective intensity criteria when the intensity of the contact is above the respective intensity threshold ( 18424 ). For example, contact  18312  meets the intensity criteria in  FIG. 8D , because the intensity of the contact is above the maintain-object-selection intensity threshold (e.g., “IT 1 ”). 
     In response ( 18420 ) to detecting the second movement of the contact across the touch-sensitive surface, in accordance with a determination that the contact does not meet the respective intensity criteria, the device moves ( 18426 ) the focus selector in accordance with the second movement of the contact across the touch-sensitive surface without moving the user interface object (e.g., detecting a successful user interface object drop). For example, in  FIGS. 8I-8J , in response to detecting movement  18318  of contact  18312  that does not meet the intensity criteria (e.g., because the intensity of contact  18312  is below IT 1 ), the device moves cursor  18310  with movement  18328  in accordance with movement  18318  but does not move thumb  18308 , as thumb  18308  is not selected. In some embodiments, the respective intensity criteria include a maintain-object-selection intensity threshold (e.g., “IT 1 ”) such that when the contact has an intensity above the maintain-object-selection intensity threshold (e.g., “IT 1 ”), the object remains selected. Conversely, when the contact has an intensity below the maintain-object-selection intensity threshold (e.g., “IT 1 ”), the object is dropped and ceases to be selected. 
     In some embodiments, the respective intensity criteria include a respective intensity threshold, and the contact does not meet ( 18428 ) the respective intensity criteria when the intensity of the contact is below the respective intensity threshold (e.g., the contact is determined not to meet the respective intensity criteria when the contact is below the IT 1  for any amount of time). For example, contact  18312  does not meet the intensity criteria if the intensity of the contact is below an intensity threshold (e.g., maintain-object-selection intensity threshold IT 1 ). In some embodiments, the respective intensity criteria include a respective intensity threshold, and the contact does not meet ( 18430 ) the respective intensity criteria when the intensity of the contact is below the respective intensity threshold for more than a predefined period of time (e.g., the contact is determined not to meet the respective intensity criteria when the contact is below the respective intensity threshold for at least 0.05, 0.1, 0.2, 0.5 seconds, or some other reasonable delay threshold). For example, contact  18312  does not meet the intensity criteria if the intensity of the contact is below the maintain-object-selection intensity threshold (e.g., “IT 1 ”) for at least the predefined period of time. 
     In some embodiments, the respective intensity criteria include a respective intensity threshold ( 18432 ). In some embodiments, the respective intensity threshold is ( 18434 ) a predefined intensity threshold (e.g., the user interface object is “dropped” if/when the intensity of the contact drops below a pre-set intensity threshold). In some embodiments, the respective intensity threshold is ( 18436 ) based on a percentage of a maximum intensity of the contact detected during the gesture. For example, the user interface object (e.g., thumb  18308 ) is “dropped” if/when the intensity of the contact (e.g., contact  18312 ) drops by 90% of a maximum intensity of the contact during the gesture. In some embodiments, the respective intensity threshold corresponds ( 18438 ) to an intensity measurement that is greater than a nominal intensity measurement (e.g., contact detection intensity threshold IT 0 ) that indicates that the contact (e.g., contact  18312 ) is in contact with the touch-sensitive surface  451 ). 
     In some embodiments, when the one or more sensors used to detect contact intensity (e.g., “intensity sensors”) are capable of measuring 4 or more quantized values of intensity, where N is the lowest quantized value of intensity (e.g., the value of intensity that corresponds to the presence of a contact on the touch-sensitive surface), the respective intensity threshold is at least one level above N. For example if there are 4 quantized values of intensity and 1 is the lowest level, then the respective intensity threshold is 2 (or some other level greater than 2). As another example, if there are 256 quantized values of intensity and 1 is the lowest level, then the respective intensity threshold is 2 (or some other level greater than 2, such as 5, 10 or 15). For example in  FIG. 8A , the device can detect and differentiate between at least a first intensity between IT 0  and IT 1 , a second intensity between IT 1  and IT L , a third intensity between IT L  and IT D  and a fourth intensity above IT D . 
     In some embodiments, while moving the respective user interface object in accordance with the second movement of the contact across the touch-sensitive surface, the device detects ( 18440 ) a liftoff of the contact from the touch-sensitive surface. In response to detecting the liftoff, the device ceases ( 18442 ) to move the respective user interface object on the display in accordance with the second movement of the contact (e.g., when the contact ceases to be detected, the device “drops” the respective user interface object, which results in movement of the respective user interface object across the display ceasing, either immediately or gradually). For example, in  FIG. 8F , while the device is moving thumb  18308  in accordance with movement  18318  of contact  18312  (as shown in  FIGS. 8C-8E ), contact  18312  is lifted off touch-sensitive surface  451 , and in response to detecting the liftoff, the device stops moving thumb  18308 . 
     As described, above, steps  18406  through  18438  are, optionally, performed while the contact is continuously detected on the touch-sensitive surface. That continuously detected contact is, optionally, lifted off, and that liftoff is detected in step  18440 . In response to detection of that liftoff, the device ceases to move the respective user interface object on the display in accordance with the second movement of the contact. Thus, in some embodiments, the object can be dropped either by lifting a contact associated with the focus selector or by reducing the intensity of the contact associated with the focus selector so that the contact does not meet the contact intensity criteria. 
     It should be understood that the particular order in which the operations in  FIGS. 9A-9C  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., those listed in the fifth paragraph of the Description of Embodiments) are also applicable in an analogous manner to method  18400  described above with respect to  FIGS. 9A-9C . For example, the contacts, user interface objects, intensity thresholds, and focus selectors described above with reference to method  18400  optionally has one or more of the characteristics of the contacts, user interface objects, intensity thresholds, and focus selectors described herein with reference to other methods described herein (e.g., those listed in the fifth paragraph of the Description of Embodiments). For brevity, these details are not repeated here. 
     In accordance with some embodiments,  FIG. 10  shows a functional block diagram of an electronic device  18500  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. 10  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. 10 , an electronic device  18500  includes a display unit  18502 ; a touch-sensitive surface unit  18504  configured to receive contacts; one or more sensor units  18505  configured to detect intensity of contacts with the touch-sensitive surface unit  18504 ; and a processing unit  18506  coupled to the display unit  18502 , the touch-sensitive surface unit  18504 , and the sensor units  18505 . In some embodiments, the processing unit  18506  includes a detecting unit  18508 , a moving unit  18510 , a determining unit  18512 , and a ceasing unit  18514 . 
     The processing unit  18506  is configured to: detect a contact with the touch-sensitive surface unit  18504 , wherein the contact is associated with a focus selector that controls movement of a respective user interface object that is currently selected (e.g., with the detecting unit  18508 ); and while continuously detecting the contact on the touch-sensitive surface unit  18504 : detect first movement of the contact across the touch-sensitive surface unit  18504  corresponding to movement of the focus selector toward a respective location (e.g., with the detecting unit  18508 ); in response to detecting the first movement of the contact across the touch-sensitive surface unit  18504 : move the focus selector on the display unit  18502  in accordance with the first movement of the contact and move the respective user interface object in accordance with the movement of the focus selector (e.g., with the moving unit  18510 ), and determine an intensity of the contact on the touch-sensitive surface unit  18504  while the focus selector is at the respective location on the display unit  18502  (e.g., with the determining unit  18512 ); detect second movement of the contact across the touch-sensitive surface unit  18504  that corresponds to movement of the focus selector away from the respective location (e.g., with the detecting unit  18508 ); and in response to detecting the second movement of the contact across the touch-sensitive surface unit  18504 : in accordance with a determination that the contact meets respective intensity criteria, move the focus selector and the user interface object in accordance with the second movement of the contact across the touch-sensitive surface unit  18504  (e.g., with the moving unit  18510 ); and in accordance with a determination that the contact does not meet the respective intensity criteria, move the focus selector in accordance with the second movement of the contact across the touch-sensitive surface unit  18504  without moving the user interface object (e.g., with the moving unit  18510 ). 
     In some embodiments, movement of the respective user interface object is constrained to a predefined path in the user interface, and moving the respective user interface object in accordance with movement of the focus selector includes moving the respective user interface object along the predefined path in accordance with a component of motion of the focus selector that corresponds to an allowed direction of motion along the predefined path. 
     In some embodiments, the respective user interface object has a two dimensional range of motion; and moving the respective user interface object in accordance with movement of the focus selector includes moving the respective user interface object to a location at or adjacent to the focus selector on the display unit  18502 . 
     In some embodiments, the respective intensity criteria include a respective intensity threshold, and the contact meets the respective intensity criteria when the intensity of the contact is above the respective intensity threshold. 
     In some embodiments, the respective intensity criteria include a respective intensity threshold, and the contact does not meet the respective intensity criteria when the intensity of the contact is below the respective intensity threshold. 
     In some embodiments, the respective intensity criteria include a respective intensity threshold, and the contact does not meet the respective intensity criteria when the intensity of the contact is below the respective intensity threshold for more than a predefined period of time. 
     In some embodiments, the respective intensity threshold is a predefined intensity threshold. 
     In some embodiments, the respective intensity threshold is based on a percentage of a maximum intensity of the contact detected during the gesture. 
     In some embodiments, the respective intensity threshold corresponds to an intensity measurement that is greater than a nominal intensity measurement that indicates that the contact is in contact with the touch-sensitive surface unit  18504 . 
     In some embodiments, the processing unit  18506  is configured to: while moving the respective user interface object in accordance with the second movement of the contact across the touch-sensitive surface unit  18504 , detect a liftoff of the contact from the touch-sensitive surface unit  18504  (e.g., with the detecting unit  18508 ); and in response to detecting the liftoff, cease to move the respective user interface object on the display unit  18502  in accordance with the second movement of the contact (e.g., with the ceasing unit  18514 ). 
     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-9C  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 10 . For example, detection operations  18402 ,  18406 , and  18418 , moving operations  18410 ,  18422 , and  18426 , and determining operation  18416  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 utilizes 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 . 
     Performing an Operation in Accordance with a Selected Mode of Operation 
     Many electronic devices have user interfaces in which multiple operations are, optionally, performed with a same type of gesture. When this gesture overloading happens within the same application, the different operations are typically associated with different modes of operation. In some methods, a user can switch between modes of operation by selecting a different mode from a menu of options or making a second contact in addition to the gesture for activating the operation. The embodiments described below improve on these methods. An operation is activated by a sequence of inputs made with a continuous contact with the touch-sensitive surface. The sequence of inputs includes increasing the intensity of the contact and moving the contact after the intensity increase. If the intensity of the contact is increased above a certain threshold, the operation that is activated is based on a different mode of operation than if the intensity is not increased above the threshold. Thus, the user can switch modes of operation smoothly, without making additional inputs, such as going through a menu or making an additional contact. 
       FIGS. 11A-11W  illustrate exemplary user interfaces for performing an operation in accordance with a selected mode of operation in accordance with some embodiments. The user interfaces in these figures are used to illustrate the processes described below, including the processes in  FIGS. 12A-12D .  FIGS. 11A-11W  include intensity diagrams that show the current intensity of the contact on the touch-sensitive surface relative to a plurality of intensity thresholds including a mode-selection intensity threshold (e.g., “IT D ”), a light press intensity threshold (e.g., “IT L ”), and an operation-cancellation threshold (e.g., “IT 1 ”). 
     In some embodiments, the device is an electronic device with a separate display (e.g., display  450 ) and a separate touch-sensitive surface (e.g., touch-sensitive surface  451 ). In some embodiments, the device is portable multifunction device  100 , the display is touch-sensitive display system  112 , and the touch-sensitive surface includes tactile output generators  167  on the display ( FIG. 1A ). For convenience of explanation, the embodiments described with reference to  FIGS. 11A-11W  and  FIGS. 12A-12D  will be discussed with reference to display  450  and a separate touch-sensitive surface  451 , however analogous operations are, optionally, performed on a device with a touch-sensitive display system  112  in response to detecting the contacts described in  FIGS. 11A-11W  on the touch-sensitive display system  112  while displaying the user interfaces shown in  FIGS. 11A-11W  on the touch-sensitive display system  112 ; in such embodiments, the focus selector is, optionally: a respective contact, a representative point corresponding to a 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 , in place of cursor  18605  or cursor  18622 . 
       FIG. 11A  illustrates user interface  18604  displayed on display  450  (e.g., display  340 , touch screen  112 ) of a device (e.g., device  300 , device  100 ). In some embodiments, user interface  18604  is a user interface for an application, such as a web browser, a word processing application, or an electronic document application. Document  18606  is displayed in user interface  18604 . Document  18606  is, for example, a web page, a word processing document, a text document, a spreadsheet, a presentation, or a drawing. A Document  18606  includes content, such as text  18608 . Text  18608  optionally has more text than can be displayed all at once. For example,  FIG. 11A  shows portion  18608 - a  of text  18608  displayed in document  18606 . A text cursor  18605  is displayed on display  450 , text cursor  18605  is an example of a focus selector. 
     The application includes two or more modes of operation. Inputs to the application (e.g., contacts or gestures detected on touch-sensitive surface  451  of the device) are, optionally, detected in accordance with a mode of operation of the application that is active at the time of detection. 
     Contact  18610  is detected on touch-sensitive surface  451  at location  18610 - a . Contact  18610  is detected as having an intensity between thresholds IT 0  and IT L . While contact  18610  is stationary on touch-sensitive surface  451 , the intensity of contact  18610  is increased to an intensity between a light press intensity threshold (e.g., “IT L ”) and a mode-change intensity threshold (e.g., “IT D ”), and the intensity increase is detected, as shown in  FIG. 11B . Then, contact  18610 , while its intensity is above an operation-cancellation intensity threshold (e.g., “IT 1 ”) and below the mode-change intensity threshold (e.g., “IT D ”), moves  18612  from location  18610 - a  to location  18610 - b  ( FIG. 11C ). In response to detection of the movement of contact  18610 , in accordance with the first mode of operation, document  18606  is scrolled, as shown in  FIG. 11C , portion  18608 - b  of text  18608  is displayed in document  18606 . 
     While contact  18610  continues to be detected on touch-sensitive surface  451  the device detects a decrease in intensity of contact  18610  below the operation-cancellation intensity threshold (e.g., “IT 1 ”), as shown in  FIG. 11D  and, in response, to detecting the decrease in intensity of contact  18610 , the device stops scrolling the document in response to movement of contact  18610 . Thus, when contact  18610  continues to move  18614  to location  18610 - c  ( FIG. 11E ), the document is not scrolled, as shown in  FIG. 11E . 
       FIG. 11F  illustrates user interface  18604 , document  18606 , and text portion  18608 - a  and text cursor  18605 , displayed on display  450 , as in  FIG. 11A . Contact  18610  is detected on touch-sensitive surface  451  at location  18610 - a  in  FIG. 11F . Contact  18610  is stationary on touch-sensitive surface  451  and has an intensity between thresholds IT 0  and IT L  in  FIG. 11F . The intensity of contact  18610  is increased to an intensity above the mode-change intensity threshold (e.g., “IT D ”), and the intensity increase is detected, as shown in  FIG. 11G . In accordance with the increase in the intensity of contact  18610  above the mode-change intensity threshold (e.g., “IT D ”), inputs are detected on touch-sensitive surface  451  in accordance with a second mode of operation that is different from the first mode of operation (e.g., the first mode of operation corresponds to document scrolling and the second mode of operation corresponds to text selection). Thus, in the example shown in  FIGS. 11F-11G , the increase in intensity of contact  18610  above the mode-change intensity threshold (e.g., “IT D ”) changed the mode of operation to the second mode of operation. 
     Contact  18610 , with the intensity above the mode-change intensity threshold (e.g., “IT D ”), moves  18616  from location  18610 - a  ( FIG. 11G ) to location  18610 - b  ( FIG. 11H ). In response to detection of the movement of contact  18610 , in accordance with the second mode of operation, text portion  18617 - a  of text  18608  is selected, as shown in  FIG. 11G . Selected text  18617 - a  is, optionally, visually emphasized (e.g., with highlighting, with an enclosure, etc.) to indicate its selection. 
     While contact  18610  continues to be detected on touch-sensitive surface  451  the device detects a decrease in intensity of contact  18610  below the operation-cancellation intensity threshold (e.g., “IT 1 ”), as shown in  FIG. 11I  and, in response, to detecting the decrease in intensity of contact  18610 , the device continues to select text in the document in response to movement of contact  18610 . Thus, when contact  18610  continues to move  18618  to location  18610 - c  ( FIG. 11J ), the selection of text continues in accordance with the movement of contact  18610  despite the detection of the decrease in the intensity of contact  18610  in  FIG. 11I . For example, text selection  18617  expands to text portion  18617 - b  in accordance with the movement of contact  18610 , as, as shown in  FIG. 11J . 
     In some embodiments, a focus selector (e.g., a text cursor  18605  or a pointer) is displayed on display  450  over document  18606 , and text selection in accordance with the second mode of operation (e.g., in response to detection of movement of contact  18610 ) starts from the location of the focus selector. 
     Thus, in some embodiments, for the same type of gesture, the mode of operation under which the contact or gesture is detected is different depending on whether the intensity of the contact is exceeded a mode-detection intensity threshold (e.g., “IT D ”). If the intensity is not increased above the mode-detection intensity threshold (e.g., “IT D ”), an operation is performed in response to detection of the gesture in accordance with a first mode of operation. If the intensity is increased above the mode-detection intensity threshold (e.g., “IT D ”), an operation is performed in response to detection of the gesture in accordance with a second mode of operation. In some embodiments, in the second mode of operation, the operation continues despite a decrease in the intensity of the input contact below an operation-cancellation threshold (e.g., “IT 1 ”) as long as the input contact continues to be detected, whereas in the first mode of operation, the operation is stopped of the intensity decreases below the operation-cancellation threshold (e.g., “IT 1 ”). 
       FIG. 11K  illustrates user interface  18618  displayed on display  450  of the device. In some embodiments, user interface  18618  is a user interface for an application, such as a drawing application or a presentation application. One or more objects  18620  are displayed in user interface  18618 . Objects  18620  are, for example, shapes in a drawing or objects (e.g., graphics, text blocks, etc.) in a presentation document. Objects  18620 - 1 ,  18620 - 2 , and  18620 - 3  are displayed in user interface  18618 . A focus selector, such as cursor  18622 , is also displayed on display  450 , at location in user interface  18618 , that is away from objects  18620  in  FIG. 11K . In some embodiments, cursor  18622  is a pointer. Inputs are detected on touch-sensitive surface  451  in accordance with a first mode of operation (e.g., the first mode of operation corresponds to dragging and dropping an object and a second mode of operation corresponds to multiple-object selection). 
     Contact  18624  is detected on touch-sensitive surface  451  at location  18624 - a  in  FIG. 11K . Contact  18624  has an intensity between thresholds IT 0  and IT L  in  FIG. 11K . Movement  18626  of contact  18624  is detected on touch-sensitive surface  18626 . In response to detection of the movement  18626  of contact  18624 , cursor  18622  moves in accordance with the movement of contact  18624 , as shown in  FIG. 11L . 
     As cursor  18622  moves in accordance with the movement of contact  18624 , cursor  18622  moves over object  18620 - 1  in  FIG. 11L . While cursor  18622  is over object  18620 - 1 , the intensity of contact  18624  is increased to an intensity between a light press intensity threshold (e.g., “IT L ”) and a mode-change intensity threshold (e.g., “IT D ”), as shown in  FIG. 11M . In response to detection of the increase in the intensity of contact  18624  in  FIG. 11M , in accordance with the first mode of operation, object  18620 - 1  is selected and “picked up” by cursor  18622 , and object  18620 - 1  moves along with cursor  18622  in accordance with the movement of contact  18624 . For example, after the intensity increase shown in  FIG. 11M , as contact  18624  continues to move  18628  and  18630  (e.g., from location  18624 - b  in  FIG. 11M  to location  18624 - c  in  FIGS. 11N-11O , then to location  18624 - d  in  FIG. 11P ), cursor  18622  moves in accordance with the movement of contact  18624  (e.g. from location  18622 - b  to location  18622 - c , then to location  18622 - d ). In accordance with movement of cursor  18622 , object  18620 - 1  moves across display  450 , as shown in  FIGS. 11M-11N . 
     In some embodiments, a tactile output is generated when the intensity of contact  18624  is increased above the light press intensity threshold (e.g., “IT L ”), indicating that object  18620 - 1  has been selected and picked up. 
     After object  18620 - 1  is selected and “picked up” in response to the detection of the increase in the intensity of contact  18624  shown in  FIG. 11M , the intensity of contact  18624  is, optionally, decreased. For example, while contact  18624  is at location  18624 - c  in  FIGS. 11N-11O , the intensity of contact  18624  is decreased to an intensity between threshold IT 0  and an operation-cancellation intensity threshold (e.g., “IT 1 ”). In response to detection of the decrease in the intensity of contact  18624  in  FIG. 11O , object  18620 - 1  is dropped and thus ceases to move on display  450  even while contact  18624  continues, as shown in  FIG. 11P . Note that, in  FIG. 11N , object  18620 - 1  is still selected even though the intensity of contact  18624  is below IT L , because the intensity of contact  18624  is still above IT 1 . 
     In some embodiments, a tactile output is generated when the intensity of contact  18624  is decreased below the operation-cancellation intensity threshold (e.g., “IT 1 ”), indicating that object  18620 - 1  has been deselected and dropped. 
       FIG. 11Q  illustrates user interface  18618  and objects  18620 - 1 ,  18620 - 2 , and  18620 - 3  displayed on display  450  of the device, as in  FIG. 11K . Objects  18620 - 1 ,  18620 - 2 , and  18620 - 3  are displayed in user interface  18618 . Cursor  18622  is also displayed at location in user interface  18618  that is away from objects  18620 . 
     Contact  18624  is detected on touch-sensitive surface  451  at location  18624 - a . Contact  18624  has an intensity between thresholds IT 0  and IT L . Movement  18632  of contact  18624  is detected on touch-sensitive surface  451 . In response to detection of the movement of contact  18624 , cursor  18622  moves in accordance with the movement  18632  of contact  18624  in  FIGS. 11Q-11R . 
     As cursor  18622  moves in accordance with the movement of contact  18624 , cursor  18622  moves over object  18620 - 1  in  FIG. 11R . While cursor  18622  is over object  18620 - 1 , the intensity of contact  18624  is increased to an intensity above a mode-change intensity threshold (e.g., “IT D ”), as shown in  FIG. 11S . In response to detection of the increase in the intensity of contact  18624  in  FIG. 11S , in accordance with the second mode of operation, object  18620 - 1  is selected. The increase in the intensity of contact  18624  changed the mode of operation to the second mode. In contrast with the first mode of operation, object  18620 - 1  is not picked up by cursor  18622 ; if cursor  18622  continues to move in accordance with movement of contact  18624 , object  18620 - 1  remains at its current location in  FIG. 11S . 
     In some embodiments, a tactile output is generated when the intensity of contact  18624  is increased above light press intensity threshold (e.g., “IT L ”) on the way to being increased above the mode-change intensity threshold (e.g., IT D ″), indicating that object  18620 - 1  has been selected. 
     After object  18620 - 1  is selected, contact  18624  continues moving  18634  in on touch-sensitive surface  451 , to location  18624 - c  ( FIG. 11T ). In accordance with the movement of contact  18624 , cursor  18622  moves over object  18620 - 2 . In accordance with cursor  18622  moving over object  18620 - 2  and in accordance with the second mode of operation, object  18620 - 2  is selected and the selection of object  18620 - 1  is maintained, so that objects  18620 - 1  and  18620 - 2  are selected as shown in  FIG. 11T . 
     In some embodiments, a tactile output is generated when cursor  18622  is moved over object  18620 - 2  while the intensity of contact  18624  is in the second mode of operation, indicating that object  18620 - 2  has been selected while maintaining selection of object  18620 - 1 . 
     After objects  18620 - 1  and  18620 - 2  are selected, the intensity of contact  18624  is, optionally, decreased. For example, while contact  18624  is at location  18624 - c , the intensity of contact  18624  is decreased to an intensity between threshold IT 0  an operation-cancellation intensity threshold (e.g., “IT 1 ”). In response to detection of the decrease in the intensity of contact  18624  in  FIG. 11U , the selection of objects  18620 - 1  and  18620 - 2  is maintained, as shown in  FIG. 11U . 
     In some embodiments, no tactile output is generated when the intensity of contact  18624  is decreased below the operation-cancellation intensity threshold (e.g., “IT 1 ”) and the selection of objects  18620 - 1  and  18620 - 2  is maintained. In some embodiments, the tactile output is not generated whether cursor  18622  is over or proximate to object  18620 - 1 , or over or proximate to object  18620 - 2 . 
     Contact  18624  moves  18636  from location  18624 - c  to location  18624 - d  on touch-sensitive surface  451 . In accordance with the movement of contact  18624 , cursor  18622  moves so that a selection area encompasses portions of objects  18620 - 1 ,  18620 - 2  and  18620 - 3 , as shown in  FIG. 11V . In accordance with cursor  18622  moving over object  18620 - 3  and in accordance with the second mode of operation, object  18620 - 3  is selected and the selection of objects  18620 - 1  and  18620 - 2  is maintained, so that objects  18620 - 1 ,  18620 - 2 , and  18620 - 3  are selected. 
     While objects  18620 - 1 ,  18620 - 2 , and  18620 - 3  are selected, the intensity of contact  18624  is decreased below threshold IT 0 , as shown in  FIG. 11W . In some embodiments, decreasing the intensity of contact  18624  below threshold IT 0  corresponds to detecting a lift off of contact  18624  from touch-sensitive surface  451 . In some embodiments, in response to detection of the decrease in the intensity of contact  18624 , objects  18620 - 1 ,  18620 - 2 , and  18620 - 3  are de-selected, as shown in  FIG. 11W . In some embodiments, in response to detection of the decrease in the intensity of contact  18624 , selection of objects  18620 - 1 ,  18620 - 2 , and  18620 - 3  is maintained. 
     While the examples described above illustrate the first operation and the second operation as different operations, in some embodiments, the first operation and the second operation are the same type of operation. For example, some embodiments, the first operation and the second operation are both text highlighting operations, but when the device is in the first mode of operation (e.g., because the contact performing the gesture did not reach or exceed IT D ) the device would stop highlighting in  FIGS. 11I-11J  when the intensity of the contact was reduced below the operation-cancellation intensity threshold (e.g., “IT 1 ”); in contrast, when the device is in the second mode of operation (e.g., because the contact performing the gesture exceeded IT D , as shown in  FIG. 11G ) the device continues highlighting, as shown in  FIGS. 11I-11J  even when the intensity of the contact is reduced below the operation-cancellation intensity threshold (e.g., “IT 1 ”). Embodiments where the first and second operations are both document scrolling operations, object selection operations, or object moving operations would be performed in an analogous manner to the highlighting example described above. 
       FIGS. 12A-12D  are flow diagrams illustrating a method  18700  of performing an operation in accordance with a selected mode of operation in accordance with some embodiments. The method  18700  is performed at an electronic device (e.g., device  300 ,  FIG. 3 , or portable multifunction device  100 ,  FIG. 1A ) with a display and a touch-sensitive surface. In some embodiments, the display is a touch screen display and the touch-sensitive surface is on the display. In some embodiments, the display is separate from the touch-sensitive surface. Some operations in method  18700  are, optionally, combined and/or the order of some operations is, optionally, changed. 
     As described below, the method  18700  provides an intuitive way to perform an operation in accordance with a selected mode of operation. The method reduces the cognitive burden on a user when performing an operation in accordance with a selected mode of operation, thereby creating a more efficient human-machine interface. For battery-operated electronic devices, enabling a user to perform an operation in accordance with a selected mode of operation faster and more efficiently conserves power and increases the time between battery charges. 
     The device displays ( 18702 ), on the display, a user interface for the electronic device. For example, in  FIG. 11A  user interface  18604  is displayed, and in  FIG. 11K  user interface  18618  is displayed. User interface  18604  includes document  18606 , and user interface  18618  includes objects  18620 . 
     The device detects ( 18704 ) a sequence of inputs on the touch-sensitive surface, where detecting the sequence of inputs includes ( 18706 ) detecting changes in characteristics (e.g., position, speed, intensity, size, rotation) of a respective contact that is continuously detected on the touch-sensitive surface during the sequence of inputs. In some embodiments, the sequence of inputs are made by a single finger contact. For example,  FIGS. 11A-11E  show a sequence of inputs involving contact  18610 . The sequence of inputs includes contact  18610 , which is continuously detected on touch-sensitive surface  451 , changing in intensity and changing position. Similar sequences of inputs are shown in  FIGS. 11F-11J  involving contact  18610 , in  FIGS. 11K-11P  involving contact  18624 , and in  FIGS. 11Q-11W  involving contact  18624 . 
     The sequence of inputs includes ( 18708 ) a first input and a second input, the first input includes ( 18710 ) detecting an increase in intensity of the respective contact (e.g., a press input), and the second input includes ( 18714 ) detecting movement of the respective contact on the touch-sensitive surface (e.g., a drag input). For example, the sequence of inputs involving contact  18610 , shown in  FIGS. 11A-11E , includes an increase in the intensity of contact  18610  (shown in  FIGS. 11A-11B ) and movement of contact  18610  (shown in  FIGS. 11B-11C ). The respective sequences of inputs involving contact  18610  ( FIGS. 11F-11J ), involving contact  18624  ( FIGS. 11K-11P ), and involving contact  18624  ( FIGS. 11Q-11W ) also include increases in contact intensity and contact movement. In some embodiments, the first input is ( 18712 ) a stationary press input. For example, in  FIGS. 11A-11B , the intensity of contact  18610  is increased while contact  18610  is stationary. 
     In response ( 18716 ) to detecting the first input, in accordance with a determination that the first input does not include increasing the intensity of the respective contact above a mode-selection intensity threshold (e.g., “IT D ”), the device operates ( 18718 ) in a first mode of operation during the second input (e.g., operating in the first (e.g., primary) mode of operation until an input, such as a deep press, that indicates a transition to the second (e.g., alternate) mode of operation is detected), and in accordance with a determination that the first input includes increasing the intensity of the respective contact above the mode-selection intensity threshold (e.g., “IT D ”), the device operates ( 18720 ) in a second mode of operation, distinct from the first mode of operation, during the second input (e.g., entering the second mode of operation while the contact is continuously detected). For example, in  FIGS. 11A-11E , the intensity of contact  18610  is increased, but not above a mode-selection intensity threshold (e.g., “IT D ”). In accordance with the intensity of contact  18610  remaining below the mode-selection intensity threshold (e.g., “IT D ”), the movement of contact  18610  is detected in accordance with a first mode of operation (e.g., corresponding to document scrolling). In  FIGS. 11F-11I , the intensity of contact  18610  is increased above the mode-selection intensity threshold (e.g., “IT D ”). In accordance with the intensity of contact  18610  increasing above the mode-selection intensity threshold (e.g., “IT D ”), the movement of contact  18610  is detected in accordance with a second mode of operation (e.g., corresponding to text selection). 
     As a further example, in  FIGS. 11J-11P , the intensity of contact  18624  is increased, but not above the mode-selection intensity threshold (e.g., “IT D ”). In accordance with the intensity of contact  18624  remaining below the mode-selection intensity threshold, the movement of contact  18624  over objects  18620  is detected in accordance with a first mode of operation (e.g., corresponding to dragging and dropping an object). In  FIGS. 11Q-11W , the intensity of contact  18624  is increased above the mode-selection intensity threshold (e.g., “IT D ”). In accordance with the intensity of contact  18624  increasing above the mode-selection intensity threshold (e.g., “IT D ”), the movement of contact  18624  over objects  18620  is detected in accordance with a second mode of operation (e.g., corresponding to multiple-object selection). 
     In some embodiments, the second mode of operation is ( 18722 ) a contact-intensity-independent mode of operation (e.g., a mode of operation where operations that would otherwise be determined based on an intensity of the contact on the touch-sensitive surface are, instead, determined based on the presence/absence of a contact on the touch-sensitive surface). For example, in  FIGS. 11U-11V , objects  18620  continue to be selected in response to cursor  18622  moving over them despite the intensity of contact  18624  decreasing below what would be for example, an operation-cancellation intensity threshold in the first mode of operation (e.g., “IT 1 ”). Selection is, optionally, cancelled (or, at least, no new object is selected whenever cursor  18622  is moved over the new object) when contact  18624  is lifted off touch-sensitive surface  451  (e.g., as shown in  FIG. 11W ). As another example, in  FIGS. 11I-11J , portions of text  18608  continue to be selected in response to movement of contact  18610  despite the intensity of contact  18610  decreasing below the operation-cancellation intensity threshold in the first mode of operation (e.g., “IT 1 ”). In either of these examples, changing the intensity of the contact, other than lift the contact off touch-sensitive surface  451 , does not affect the operation. 
     In response to detecting the second input, the device performs ( 18724 ) an operation in accordance with the second input based at least in part on whether the device is operating in the first mode of operation or the second mode of operation. For example, in  FIGS. 11B-11C , document  18606  is scrolled, in accordance with a first mode of operation, in response to detection of the movement of contact  18610 , and in  FIGS. 11G-11J , portions of text  18608  are selected, in accordance with a second mode of operation, in response to movement of contact  18610 . As another example, in  FIGS. 11M-11P , object  18620 - 1  is dragged and dropped, in accordance with a first mode of operation, in response to movement of contact  18624 . In  FIGS. 11S-11V , objects  18620 - 1  through  18620 - 3  are selected, in accordance with a second mode of operation, in response to movement of contact  18624 . 
     In some embodiments, while ( 18726 ) in the first mode of operation, the device starts ( 18728 ) to perform a first operation corresponding to the second input, the device detects ( 18730 ) a decrease in intensity of the contact below a respective intensity threshold (e.g., IT L , IT 1 , or a hysteresis intensity threshold associated with IT L  that is below IT L ), and in response to detecting the decrease in intensity of the contact below the respective intensity threshold (e.g., IT L , IT 1 , or a hysteresis intensity threshold associated with IT L  that is below IT L ) while in the first mode of operation, the device ceases ( 18732 ) to perform the first operation (e.g., the device determines whether to continue moving an object or drop the object based on whether the intensity of the contact on the touch-sensitive surface drops below the operation-cancellation intensity threshold IT 1  for the first mode of operation). 
     For example, in  FIGS. 11B-11C , document  18606  is being scrolled in response to detection of the movement of contact  18610 , where contact  18610  has an intensity between thresholds IT 1  and IT D . While document  18606  is being scrolled, the intensity of contact  18610  decreases below a respective threshold (e.g., “IT 1 ”). In response to detection of the decrease in the intensity of contact  18610  in  FIG. 11D  while the device is in the first mode of operation, document  18606  ceases to be scrolled, as shown in  FIG. 11E , however, in some embodiments, if the device had been in the second mode of operation, the device would have continued to scroll the document. 
     In another example, in  FIGS. 11L-11N , object  18620 - 1  is selected, picked up, and dragged in response to detection of a gesture including the movement of cursor  18622  over object  18620 - 1 . While object  18620 - 1  is being dragged, the intensity of contact  18624  decreases below a respective threshold (e.g., threshold IT 1 ). In response to detection of the decrease in the intensity of contact  18624  in  FIG. 11O  while the device is in the first mode of operation, object  18620 - 1  is dropped in user interface  18618  as shown in  FIGS. 11O-11P , however in some embodiments, if the device had been in the second mode of operation, the device would have continued to drag object  18620 - 1 . 
     In some embodiments, the device, while ( 18734 ) in the second mode of operation, the device starts ( 18736 ) to perform a second operation corresponding to the second input, the device detects ( 18738 ) a decrease in intensity of the contact below the respective intensity threshold (e.g., IT L , IT 1 , or a hysteresis intensity threshold associated with IT L ), and in response to detecting the decrease in intensity of the contact below the respective intensity threshold (e.g., IT L , IT 1 , or a hysteresis intensity threshold associated with IT L ) while in the second mode of operation, the device continues ( 18740 ) to perform the second operation (e.g., the device continues to move an object based even if intensity of the contact on the touch-sensitive surface drops below the operation-cancellation intensity threshold IT 1  for the first mode of operation). 
     For example, in  FIGS. 11G-11J , a portion of text  18608  is selected in response to detection of the gesture including movement of contact  18610 , and while additional text  18608  continues to be selected, the intensity of contact  18610  decreases below a respective threshold (e.g., “IT 1 ”). In response to detection of the decrease in the intensity of contact  18610  in  FIG. 11I  while the device is in the second mode of operation, additional text  18608  continues to be selected in response to movement  18618  of contact  18610  in  FIGS. 11I-11J , however in some embodiments, if the device had been in the first mode of operation the device would have stopped selecting the text in response to detecting the decrease in intensity of contact  18610  below IT 1  in  FIG. 11I . 
     In another example, in  FIGS. 11Q-11V , object  18620 - 1  is selected in response to detection of the movement of cursor  18622  over object  18620 - 1 , and while cursor  18622  continues moving in response to movement of contact  18624 , the intensity of contact  18624  decreases below a respective threshold (e.g., “IT 1 ”). In response to detection of the decrease in the intensity of contact  18624  in  FIG. 11U  while the device is in the second mode of operation, the device continues to select additional objects (e.g., objects  18620 - 2  and  18620 - 3 ) when cursor  18622  is moved over them, however in some embodiments, if the device had been in the first mode of operation the device would have stopped selecting the objects in response to detecting the decrease in intensity of contact  18624  below IT 1  in  FIG. 11U . 
     In some embodiments, in the first mode of operation, the second input corresponds to ( 18742 ) a first operation (e.g., dropping an object), and in the second mode of operation, the second input corresponds to a second operation different from the first operation (e.g., continuing to move the object). Thus, in some embodiments, the second input has a different meaning in the first mode of operation than it does in the second mode of operation. For example, in  FIGS. 11K-11P , movement of a contact in the first mode of operation corresponds to dragging-and-dropping an object (e.g., movement of contact  18624 ), however, in some embodiments, in the second mode of operation (e.g., where contact  18624  exceeds IT D ), the device would continue to move object  18620 - 1  even after the intensity of contact  18624  decreased below the operation-cancellation intensity threshold (e.g., “IT 1 ”), until liftoff of contact  18624  is detected. 
     In some embodiments, the first operation includes ( 18744 ) scrolling an electronic document, and the second operation includes selecting content in the electronic document. For example, in  FIGS. 11A-11J , movement of a contact in the first mode of operation corresponds to document scrolling (e.g., movement of contact  18610  in  FIGS. 11A-11E ), and movement of the contact in the second mode of operation corresponds to content (e.g., text) selection (e.g., movement of contact  18610  in  FIGS. 11F-11J ). 
     In some embodiments, the first operation includes ( 18746 ) moving a user interface object in a user interface, and the second operation includes selecting a plurality of user interface objects in the user interface. For example, while in the first mode of operation, the device deselects a currently selected user interface object upon detecting a decrease of intensity of a contact below an object-deselection intensity threshold (e.g., “IT 1 ”). Conversely, while in the second mode of operation, the device maintains selection of the currently selected user interface object even after detecting a decrease in intensity of the contact below the object-deselection intensity threshold (e.g., “IT 1 ”) until liftoff of the contact, another deep press gesture, or other predefined input is detected that exits the second mode of operation. In  FIGS. 11K-11W , movement of a contact in the first mode of operation corresponds to moving (e.g., dragging-and-dropping) an object (e.g., movement of contact  18624  in  FIGS. 11K-11Q ), and movement of the contact in the second mode of operation corresponds to multiple-object selection (e.g., movement of contact  18624  in  FIGS. 11Q-11V ). 
     In some embodiments, in response to detecting the first input, the device starts ( 18748 ) to perform a respective operation (e.g., “pick up and move” a user interface object), and in response to detecting the second input, the device continues to perform the respective operation (e.g., “continue to move” the previously picked up user interface object). For example, in  FIGS. 11K-11P , object  18620 - 1  is “picked up” in response to an increase in the intensity of contact  18624  above threshold IT L  while cursor  18622  is over object  18620 - 1 , and object  18620 - 1  is moved in response to movement  18628  of contact  18624  after object  18620 - 1  is picked up. 
     In some embodiments, the device detects ( 18750 ) an increase in intensity of the respective contact above a first intensity threshold (e.g., an object-selection intensity threshold such as IT L ) while a focus selector corresponding to the contact is at or proximate to a respective user interface object. In response to detecting the increase in intensity of the respective contact above the first intensity threshold (e.g., IT L  or IT D ), the device generates ( 18752 ) a tactile output on the touch-sensitive surface that corresponds to selection of the respective user interface object. After ( 18754 ) detecting the increase in intensity of the respective contact above the first intensity threshold (e.g., IT L  or IT D ), the device detects ( 18756 ) a decrease in intensity of the respective contact below a second intensity threshold (e.g., an object-drop intensity threshold such as IT 1 ) while the focus selector is at or proximate to the respective user interface object. In response to detecting the decrease in intensity of the respective contact below the second intensity threshold (e.g., IT L , IT 1  or a hysteresis threshold associated with IT L  that is below IT L ), in accordance with the determination that the device is in the first mode of operation, the device deselects ( 18758 ) the respective user interface object and generates ( 18760 ) a tactile output corresponding to deselecting the respective user interface object; and in accordance with the determination that the device is in the second mode of operation, the device maintains ( 18762 ) selection of the respective user interface object and forgoes generation of the tactile output corresponding to deselecting the respective user interface object. 
     For example, in  FIGS. 11K-11P , a tactile output is optionally generated in response to the increase in the intensity of contact  18624  above a first intensity threshold (e.g., “IT L ”) while cursor  18622  is over object  18620 - 1  in  FIG. 11M  (indicating selection and pick-up of object  18620 - 1 ), and a tactile output is optionally generated in response to the decrease in the intensity of contact  18624  below a second intensity threshold (e.g., “IT 1 ”) while cursor  18622  is over object  18620 - 1  in  FIG. 11O  (indicating de-selection and dropping of object  18620 - 1 ). In  FIGS. 11Q-11W , a tactile output is optionally generated in response to the increase in the intensity of contact  18624  above threshold IT L  while cursor  18622  is over object  18620 - 1  in  FIG. 11S  (indicating selection of object  18620 - 1 ), and a tactile output is not generated in response to the decrease in the intensity of contact  18624  below second intensity threshold (e.g., “IT 1 ”) but remaining above threshold IT 0  (e.g., because the device does not drop or de-select object  18620 - 1 ) in  FIG. 11V . 
     Thus, in some embodiments, while the device is in the first mode of operation, the device generates tactile outputs so that the user feels a click when increasing past an object-pickup intensity threshold and also when decreasing past an object-drop intensity threshold (e.g., because objects are being picked up and dropped). In contrast, while the device is in the second mode of operation, the device generates tactile outputs so that the user feels a click when increasing past an object-pickup intensity threshold, but does not feel a click when decreasing past object-drop intensity threshold (because objects are not being dropped). Thus, in some embodiments, the first mode of operation provides similar tactile outputs to those that would be expected from a physical actuator, while the second mode of operation provides tactile outputs that correspond more closely to the operations being performed in the user interface, even if additional tactile outputs that would have been generated by a physical actuator are not performed (e.g., the device has the ability to output multiple “down click” tactile outputs without outputting a corresponding number of “up click” tactile outputs). 
     It should be understood that the particular order in which the operations in  FIGS. 12A-12D  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., those listed in the fifth paragraph of the Description of Embodiments) are also applicable in an analogous manner to method  18700  described above with respect to  FIGS. 12A-12D . For example, the contacts, user interface objects, tactile outputs, intensity thresholds, and focus selectors described above with reference to method  18700  optionally have one or more of the characteristics of the contacts, user interface objects, tactile outputs, intensity thresholds, and focus selectors described herein with reference to other methods described herein (e.g., those listed in the fifth paragraph of the Description of Embodiments). For brevity, these details are not repeated here. 
     In accordance with some embodiments,  FIG. 13  shows a functional block diagram of an electronic device  18800  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  18800  includes a display unit  18802  configured to display a user interface for the electronic device, a touch-sensitive surface unit  18804  configured to receive inputs, one or more sensors  18806  configured to detect intensity of contacts with the touch-sensitive surface unit  18804 , and a processing unit  18808  coupled to the display unit  18802 , the touch-sensitive surface unit  18804 , and the sensors  18806 . In some embodiments, the processing unit  18808  includes a detecting unit  18810 , an operating unit  18812 , a performing unit  18814 , a starting unit  18816 , a ceasing unit  18818 , a continuing unit  18820 , a generating unit  18822 , a deselecting unit  18824 , and a maintaining unit  18826 . 
     The processing unit  18808  is configured to: detect a sequence of inputs on the touch-sensitive surface unit  18804  (e.g., with the detecting unit  18810 ), wherein: detecting the sequence of inputs includes detecting changes in characteristics of a respective contact that is continuously detected on the touch-sensitive surface unit  18804  during the sequence of inputs, the sequence of inputs includes a first input and a second input, the first input includes detecting an increase in intensity of the respective contact, and the second input includes detecting movement of the respective contact on the touch-sensitive surface unit  18804 ; in response to detecting the first input: in accordance with a determination that the first input does not include increasing the intensity of the respective contact above a mode-selection intensity threshold (e.g., “IT D ”), operate in a first mode of operation during the second input (e.g., with the operating unit  18812 ), and in accordance with a determination that the first input includes increasing the intensity of the respective contact above the mode-selection intensity threshold (e.g., “IT D ”), operate in a second mode of operation, distinct from the first mode of operation, during the second input (e.g., with the operating unit  18812 ); and in response to detecting the second input, perform an operation in accordance with the second input based at least in part on whether the device is operating in the first mode of operation or the second mode of operation (e.g., with the performing unit  18814 ). 
     In some embodiments, the first input is a stationary press input. 
     In some embodiments, the second mode of operation is a contact-intensity-independent mode of operation. 
     In some embodiments, the processing unit  18808  is configured to, while in the first mode of operation: start to perform a first operation corresponding to the second input (e.g., with the starting unit  18816 ), detect (e.g., with the detecting unit  18810 ) a decrease in intensity of the contact below a respective intensity threshold (e.g., “IT 1 ”), and in response to detecting the decrease in intensity of the contact below the respective intensity threshold (e.g., “IT 1 ”) while in the first mode of operation, cease to perform the first operation (e.g., with the ceasing unit  18818 ). 
     In some embodiments, the processing unit  18808  is configured to, while in the second mode of operation: start to perform a second operation corresponding to the second input (e.g., with the starting unit  18816 ), detect (e.g., with the detecting unit  18810 ) a decrease in intensity of the contact below the respective intensity threshold (e.g., “IT 1 ”), and in response to detecting the decrease in intensity of the contact below the respective intensity threshold (e.g., “IT 1 ”) while in the second mode of operation, continue to perform the second operation (e.g., with the continuing unit  18820 ). 
     In some embodiments, in the first mode of operation, the second input corresponds to a first operation, and in the second mode of operation, the second input corresponds to a second operation different from the first operation. 
     In some embodiments, the first operation includes scrolling an electronic document, and the second operation includes selecting content in the electronic document. 
     In some embodiments, the first operation includes moving a user interface object in a user interface, and the second operation includes selecting a plurality of user interface objects in the user interface. 
     In some embodiments, the processing unit  18808  is configured to: in response to detecting the first input, start to perform a respective operation (e.g., with the starting unit  18816 ), and in response to detecting the second input, continue to perform the respective operation (e.g., with the continuing unit  18820 ). 
     In some embodiments, the processing unit  18808  is configured to: detect an increase in intensity of the respective contact above a first intensity threshold (e.g., IT L  or IT D ) while a focus selector corresponding to the contact is at or proximate to a respective user interface object (e.g., with the detecting unit  18810 ); in response to detecting the increase in intensity of the respective contact above the first intensity threshold (e.g., IT L  or IT D ), generate a tactile output on the touch-sensitive surface unit  18804  that corresponds to selection of the respective user interface object (e.g., with the generating unit  18822 ); and after detecting the increase in intensity of the respective contact above the first intensity threshold (e.g., IT L  or IT D ): detect a decrease in intensity of the respective contact below a second intensity threshold (e.g., IT L , IT 1  or a hysteresis threshold associated with IT L  that is below IT L ) while the focus selector is at or proximate to the respective user interface object (e.g., with the detecting unit  18810 ), and in response to detecting the decrease in intensity of the respective contact below the second intensity threshold (e.g., IT L , IT 1  or a hysteresis threshold associated with IT L  that is below IT L ): in accordance with the determination that the device is in the first mode of operation, deselect the respective user interface object (e.g., with the deselecting unit  18824 ) and generating a tactile output corresponding to deselecting the respective user interface object (e.g., with the generating unit  18822 ), and in accordance with the determination that the device is in the second mode of operation, maintain selection of the respective user interface object (e.g., with the maintain unit  18826 ) and forgo generation of the tactile output corresponding to deselecting the respective user interface object (e.g., with the generating unit  18822 ). 
     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. 12A-12D  are, optionally, implemented by components depicted in  FIGS. 1A-1B  or  FIG. 13 . For example, detection operation  18704 , operating operations  18718  and  18720 , and performing operation  18724  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 corresponds to a predefined event or sub-event, such as selection of an object on a user interface. 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 utilizes 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 . 
     It should be understood that the particular order in which the operations have been described above 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 the various processes separately described herein (e.g., those listed in the fifth paragraph of the Description of Embodiments) can be combined with each other in different arrangements. For example, the contacts, user interface objects, tactile sensations, intensity thresholds, and/or focus selectors described above with reference to any one of the various processes separately described herein (e.g., those listed in the fifth paragraph of the Description of Embodiments) optionally have one or more of the characteristics of the contacts, gestures, user interface objects, tactile sensations, intensity thresholds, and focus selectors described herein with reference to one or more of the other methods described herein (e.g., those listed in the fifth paragraph of the Description of Embodiments). For brevity, all of the various possible combinations are not specifically enumerated here, but it should be understood that the claims described above may be combined in any way that is not precluded by mutually exclusive claim features. 
     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 various described embodiments 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 various described embodiments and their practical applications, to thereby enable others skilled in the art to best utilize the various described embodiments with various modifications as are suited to the particular use contemplated.