PATENT DOCUMENT

Publication Number: US-9494980-B2
Application Number: US-201514622419-A
Country: US
Kind Code: B2

Title: Magnetic attachment unit

Abstract:
A magnetic attachment mechanism and method is described. The magnetic attachment mechanism can be used to releasably attach at least two objects together in a preferred configuration without fasteners and without external intervention. The magnetic attachment mechanism can be used to releasably attach an accessory device to an electronic device. The accessory device can be used to augment the functionality of usefulness of the electronic device.

Claims:
The invention claimed is: 
     
       1. An accessory device, comprising:
 a stylus that is separable from a magnetic attachment feature having a body that carries a magnet that is arranged to magnetically attach to a host device; and 
 an electronic circuit that acts in concert with the host device that enables the host device to perform a host device function only when the host device and the body are magnetically attached to each other using the magnet, otherwise, the host device is incapable of performing the host device function. 
 
     
     
       2. The accessory device as recited in  claim 1 , wherein the host device is a tablet computer. 
     
     
       3. The accessory device as recited in  claim 1 , wherein in response to the magnetic attachment of the body to the host device using the magnet, the host device is operable in a stylus input recognition mode. 
     
     
       4. The accessory device as recited in  claim 3 , wherein in the stylus input recognition mode, the host device is operable in accordance with movement of the stylus. 
     
     
       5. The accessory device as recited in  claim 1 , wherein the electronic circuit comprises a data storage device arranged to store at least information used by the host device. 
     
     
       6. The accessory device as recited in  claim 1 , wherein the electronic circuit comprises an RF trx/rx antenna system. 
     
     
       7. The accessory device as recited in  claim 1 , wherein the electronic circuit comprises a camera. 
     
     
       8. A consumer product system, comprising:
 a tablet device having a housing that carries a processor, the housing including an opening in accordance with a full front side of the tablet device and an optically clear protective layer carried by the housing within the opening that overlays a display configured for presenting visual content; and 
 an accessory device, comprising: 
 a stylus that is separable from a magnetic attachment feature arranged to magnetically attach to the tablet device, and 
 an electronic circuit in communication with the tablet device only when the accessory device is magnetically attached to an external surface of the housing using the magnetic attachment feature, wherein the communication between the tablet device and the electronic circuit enables the tablet device to perform a tablet device function, otherwise, the tablet device is incapable of performing the tablet device function. 
 
     
     
       9. The consumer product system as recited in  claim 8 , wherein the tablet device function is a stylus input recognition mode rendering the tablet device operable to respond to movement of the stylus with respect to the optically clear protective layer. 
     
     
       10. The consumer product system as recited in  claim 9 , wherein the tablet device responds to movement of the stylus with respect to the optically clear protective layer by the display rendering visual content in accordance with the movement. 
     
     
       11. The consumer product system as recited in  claim 8  further comprising a sensor coupled with the processor and arranged to detect the presence of a triggering magnet at the external surface of the housing indicating that the accessory device is magnetically attached to the external surface of the housing. 
     
     
       12. An accessory device, comprising:
 a stylus that is separable from a magnetic attachment feature arranged to magnetically attach to a host device; and 
 an electronic circuit that acts in concert with the host device that enables the host device to perform a host device function when the host device and the stylus are magnetically attached to each other using the magnetic attachment feature, otherwise, the host device is incapable of performing the host device function. 
 
     
     
       13. The accessory device as recited in  claim 12 , wherein the host device is a tablet computer. 
     
     
       14. The accessory device as recited in  claim 12 , wherein the stylus carries the electronic circuit. 
     
     
       15. The accessory device as recited in  claim 12 , wherein in response to the magnetic attachment of the stylus to the host device, the host device is operable in a stylus input recognition mode. 
     
     
       16. The accessory device as recited in  claim 15 , wherein in the stylus input recognition mode, the host device operates in accordance with a movement of the stylus.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 14/003,223, filed Oct. 24, 2013, entitled “MAGNETIC ATTACHMENT UNIT”, which is a national stage application under 35 U.S.C. §371 and claims priority under 35 U.S.C. §119(b) to PCT Application No. PCT/US2012/023025, filed Jan. 27, 2012, entitled “MAGNETIC ATTACHMENT UNIT”, which claims the benefit of U.S. Provisional Application No. 61/438,220, filed Jan. 31, 2011, entitled “MAGNETIC ATTACHMENT UNIT AND METHODS OF USE”, the contents of which are incorporated herein by reference in their entirety for all purposes. 
    
    
     FIELD 
     The described embodiments generally relate to portable electronic devices. More particularly, the present embodiments describe releasable attachment techniques well suited for portable electronic devices. 
     BACKGROUND 
     Recent advances in portable computing includes the introduction of hand held electronic devices and computing platforms along the lines of the iPad™ tablet manufactured by Apple Inc. of Cupertino, Calif. These handheld computing devices can be configured such that a substantial portion of the electronic device takes the form of a display used for presenting visual content leaving little available space for an attachment mechanism that can be used for attaching an accessory device. 
     Conventional attachment techniques generally rely upon mechanical fasteners that typically require at least an externally accessible attaching feature on the electronic device to mate with a corresponding attaching feature on the accessory device. The presence of the external attaching feature can detract from the overall look and feel of the handheld computing device as well as add unwanted weight and complexity as well as degrade the appearance of the hand held computing device. 
     Therefore a mechanism for releasably attaching together at least two objects is desired. 
     SUMMARY 
     This paper describes various embodiments that relate to a system, method, and apparatus for forming a cooperative system using magnetic attachment. 
     A magnetic attachment unit for magnetically attaching together a first object having a first magnetic attachment system and a second object having a second magnetic attachment system to form a cooperative system is described. The magnetic attachment unit includes at least a magnetic attachment system that is arranged to provide a first activation force for activating the first magnetic system and a second activation force for activating the second magnetic system. The activated first and second magnetic systems cooperate with the magnetic attachment system to releasably secure the first object and the second object together to form the cooperating magnetic system. 
     A magnetic attachment unit for magnetically attaching together at least individual first electronic and second electronic devices each having an associated magnetic attachment feature, the magnetically attached electronic devices communicating with each other to when magnetically attached to form a cooperative electronic system. The magnetic attachment unit includes a body having a first side and a second side opposite the first side, a first magnetic attachment system at a first side of the body comprising at least a first magnet arranged to provide a first activation force for activating a corresponding magnetic attachment feature in the first electronic device, and a second magnetic attachment system at a second side of the body comprising at least a second magnet arranged to provide a second activation force for activating a corresponding magnetic attachment feature in the second electronic device, wherein a magnetic attachment force generated between the activated first and second magnetic systems and the corresponding magnets in the magnetic attachment unit results in the first and second individual electronic devices to operable together as a cooperating electronic device. 
     A cover assembly is described that includes at least a hinge assembly detachably connected to a host unit and a cover assembly pivotally attached to hinge assembly having a size and shape in accordance with the host unit. The cover assembly includes at least a cover portion pivotally attached to the hinge portion at a first pivot, a flap portion separate from the cover portion pivotally attached to the hinge portion at a second pivot different from the first pivot such that the cover portion and the flap portion rotate about their respective pivot points separately in such that the cover forms a support structure that supports the host device at an inclined angle with respect to the flap portion. 
     A docking station includes at least a base portion arranged to provide support for a host device, the base portion includes an attachment unit, the attachment unit arranged to detachably secure the host device and the base portion, a user input portion, the user input portion arranged to receive a user input event, and a communication port, the communication port arranged to provide a communication path between the host device and the user input portion of the base portion, wherein information associated with the user input event at the user input portion is passed by way of the communication path provided by the communication port to the host device. 
     Other aspects and advantages of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the described embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIG. 1  is a simplified block diagram of an article and an electronic device that can be releasably attached to each other in a desired and repeatable manner. 
         FIG. 2A  is a simplified perspective view of an article that can be releasably attached to an electronic device via a side magnetic attachment system, in accordance with one described embodiment. 
         FIG. 2B  shows the article and the electronic device of  FIG. 2A  attached in accordance with the side magnetic attachment system. 
         FIG. 3A  is a simplified perspective view of a first electronic device that can be releasably attached to a second electronic device via a side magnetic attachment system, in accordance with one described embodiment. 
         FIG. 3B  shows the first electronic device and the second electronic device of  FIG. 3A  attached in accordance with the side magnetic attachment system to form a cooperating electronic system. 
         FIGS. 4A and 4B  are simplified perspective views of an article that can be releasably attached to an electronic device via magnetic attachment unit and corresponding magnetic system. 
         FIGS. 5A and 5B  are simplified perspective views of an article in the form of electronic device that can be releasably attached to an electronic device via magnetic attachment unit. 
         FIG. 6A  shows a top perspective view of electronic device  100  in accordance with the described embodiments. 
         FIG. 6B  shows activated magnetic attachment feature. 
         FIGS. 7A-7B  show magnetic attachment unit used to magnetically attach electronic devices to form cooperating system. 
         FIGS. 8A-8C  show various embodiments of magnetic attachment unit that can be used to magnetically attach electronic device to an object having a suitably configured magnetic attachment system. 
         FIG. 9  illustrates an arrangement formed by magnetically attaching tablet device and tablet device by way of flexible magnetic attachment unit in an open configuration. 
         FIG. 10  shows arrangement in a closed configuration in which a tablet device uses the flexible nature of flexible connecting member to fold atop one another. 
         FIGS. 11A and 11B  show tablet devices magnetically attached to each other by way of magnetic attachment unit. 
         FIGS. 12A-12C  show tablet device connected together by way of magnetic attachment unit. 
         FIG. 13  shows magnetic attachment unit magnetically attaching tablet devices to form tablet array. 
         FIGS. 14A-14B  show a cross section of system in accordance with an embodiment. 
         FIGS. 15-17  show various embodiments of flap portion of cover assembly. 
         FIGS. 18A-18D  show fixed magnetic docking station in accordance with the described embodiments. 
         FIGS. 19A-19B  show pivoting magnetic docking station in accordance with the described embodiments. 
         FIGS. 20A-20F  show various hanging accessories in accordance with the described embodiments. 
         FIGS. 21A and 21B  show additional hanging accessories in accordance with the described embodiments. 
         FIG. 22A  shows a vehicle mount in accordance with the described embodiments. 
         FIG. 22B  shows a tread mill mount in accordance with the described embodiments. 
         FIGS. 23A-23H  show various accessories in accordance with the described embodiments. 
         FIG. 24  shows a travel case in accordance with the described embodiments. 
         FIG. 25A-25B  show electromagnetic release mechanism. 
         FIGS. 26A-26C  show a hands free approach to altering an operating state of an electronic device. 
         FIGS. 27A-27B  show hands free ejection embodiment. 
         FIGS. 28A-28B  show a magnetic window embodiment. 
         FIGS. 29A-29B  shows another embodiment of a magnetic attachment feature. 
         FIGS. 30A-30B  show still another embodiment of the magnetic attachment feature of  FIGS. 29A-29B . 
         FIGS. 31A-31C  show the magnetic attachment feature of  FIGS. 30A-30B  arranged to provide magnetic attachment information. 
         FIG. 32A  shows an embodiment of a representative magnetic element of the magnetic attachment feature of  FIGS. 31A-31C  providing a first type information. 
         FIG. 32B  shows an embodiment of the representative magnetic element of the magnetic attachment feature of  FIGS. 31A-31C  providing a second type information. 
         FIG. 33  shows a table of representative attachment status according to information provided by the magnetic attachment feature of  FIGS. 31A-31B . 
         FIG. 34  is a block diagram of an arrangement of functional modules utilized by a portable media device. 
         FIG. 35  is a block diagram of an electronic device suitable for use with the described embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following descriptions are not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims. 
     The following description relates in general to a mechanism that can be used to attach together at least two suitably configured objects. In one embodiment, this can be accomplished without the use of conventional fasteners. Each of the objects can include an attachment feature arranged to provide a magnetic field having appropriate properties. When the attachment features are brought into proximity with each other, the magnetic fields can cooperatively interact based upon their respective properties and can result in the objects magnetically attaching to each other in a desired and repeatable manner. For example, due at least in part to the cooperative nature of the interaction of the magnetic fields, the objects can attach to each other in a pre-determined position and relative orientation without external intervention. For example, the cooperative magnetic interaction can result in the objects self-aligning and self-centering in a desired orientation. 
     The objects can remain in the magnetically attached state if and until a releasing force of sufficient magnitude is applied that overcomes the overall net attractive magnetic force. In some cases, however, it can be desirable to detach the objects serially (along the lines of a zipper) in which case, the releasing force only need be of sufficient magnitude to overcome the net magnetic attractive force of one pair of magnetic elements at a time. Connectors such as mechanical fasteners are not required to attach the objects together. Furthermore, to prevent undue interference to the magnetic interaction between the magnetic attachment features, at least a portion of the objects in the vicinity of the magnetic attachment features can be formed of magnetically inactive materials such as plastic or non-ferrous metals such as aluminum or non-magnetic stainless steel. 
     The objects can take many forms and perform many functions. When magnetically attached to each other, the objects can communicate and interact with each other to form a cooperating system. The cooperating system can perform operations and provide functions that cannot be provided by the separate objects individually. In another embodiment, at least one device can be used as an accessory device. The accessory device can be magnetically attached to at least one electronic device. The accessory device can provide services and functions that can be used to enhance the operability of the electronic device(s). For example, the accessory device can take the form of a protective case that can be magnetically attached to the electronic device and enclose the electronic device. The protective case can provide protection to certain aspects (such as a display) of the electronic device as well as to the electronic device as a whole. The magnetic attachment mechanism used to magnetically attach the protective case and the electronic device can assure that the protective case can only attach to the electronic device in a specific orientation. Moreover, the magnetic attachment mechanism can also assure proper alignment and positioning of the protective case and the electronic device. 
     In one embodiment, a first object and a second object can be magnetically attached to each other such that the first object can be configured to provide a support mechanism to the second object. The support mechanism can be mechanical in nature. For example, the first object can take the form of a stand that can be used to support the second object on a working surface such as a table. In one embodiment, the stand can take the form of an articulating stand arranged to present the second object in a number of angles and orientations. 
     In one embodiment, the first object can take the form of a dock arranged to magnetically attach to the second object in a particular manner. The dock can be electronic in nature in those cases where the second object is an electronic device. The dock can provide an electrical contact that can provide power from an external power supply to the electronic device. The electrical contact can also provide a mechanism by which information can be provided to the electronic device and as well as information provided from the electronic device. For example, the dock can include audio output devices such as speakers arranged to broadcast sound based upon an audio signal received from the electronic device. 
     In one embodiment, the first object can take the form of a hanging apparatus. As such, the first object can be used to hang the second object that can then be used as a display for presenting visual content such as a visual, still images like a picture, art work, and so on. The support mechanism can also be used as a handle for conveniently grasping or holding the second object. This arrangement can be particularly useful when the second object can present visual content such as images (still or visual), textual (as in an e-book) or has image capture capabilities in which case the second object can be used as an image capture device such as a still or visual camera and the first object can be configured to act as a support such as a tripod or handle. The handle can be fixed or flexible. In one embodiment, the hanging apparatus can take the form of hooks, suction cups, or any other appropriate hanging device. For example, the hanging apparatus can be used to secure the electronic device to a whiteboard. In one embodiment, the hanging apparatus in the form of a hook can be used to secure the electronic device to a seat cushion in an automobile, plane, or train. In this way, the electronic device can provide visual content for those seated in a position to view the display screen. 
     In one embodiment, the attachment can occur between a first and second object where the first object and second object are each electronic devices. The electronic devices can be magnetically attached to each other to form a cooperative electronic system in which the electronic devices can communicate with each other. In one embodiment, the first and second electronic devices can be attached to each other directly. In one embodiment, a magnetic attachment unit can be used to magnetically attach together the first and second electronic devices. Communication between the first and second electronic devices can occur before, during, and after the magnetic attachment is complete. 
     As part of this communication, information can be passed between the first and second electronic devices. The information can be processed in whole or in part at either the first or second electronic device depending upon the nature of the processing. In this way, the cooperative electronic system can take advantage of the synergistic effect of having multiple electronic devices magnetically attached and in communication with each other. In one implementation, the communication can be carried out wirelessly using any suitable wireless communication protocol such as Bluetooth (BT), GSM, CDMA, WiFi, and so on. 
     In one embodiment, the magnetic attachment unit can pass information between the first and second electronic devices. In one embodiment, information can be provided from the magnetic attachment unit and pass to one or both of the first and second electronic devices. For example, in one embodiment, the magnetic attachment unit can take the form of a magnetic binder that can be used to attach the first and second electronic devices in the form of an electronic book. As such, at least one electronic device can have a display suitable for presented visual content. Information, such as book content, can pass from the magnetic binder to the electronic device. The information can cause the electronic device to operate in a manner consistent with the information. 
     For example, when information provided to the first and or second electronic device is associated with a specific learning tutorial (such as math, languages, etc.), the information can cause one or both of the electronic devices to operate in a manner consistent with the tutorial, such as presenting lessons, work sheets, and so forth. For example, the first electronic device can present visual content consistent with the subject matter of the tutorial while the second electronic device can facilitate user interaction by presenting a user input such as a virtual keyboard, touch input, and so on. 
     In one embodiment, the second electronic device can take the form of a peripheral device such as a keyboard, touch pad, joystick, and so forth. This embodiment can be well suited for video games presented by the first electronic device. In one embodiment, the magnetic attachment unit can store the information required to initiate the video game whereas in another embodiment, the magnetic attachment unit can act as a trigger. The trigger acting to initiate a game resident on either or both the first and second electronic devices. 
     In one embodiment, the cooperative electronic system can take the form of an array of electronic devices rigidly connected to each other by way of the magnetic attachment unit. The magnetic attachment unit can include a plurality of magnetic attachment features. Each of the plurality of magnetic attachment features can magnetically interact with a corresponding magnetic attachment feature including in a corresponding electronic device. In one embodiment, the array of electronic devices can act as a single unified display (along the lines of a mosaic). In another embodiment, the array of electronic devices can provide a single or a set of functions (such as virtual keyboard). 
     As an example, a first and second electronic device can be magnetically coupled together by way of a magnetic attachment unit. The magnetic attachment unit can include a magnetic system. In one embodiment, the magnetic attachment unit can act as a trigger to activate a magnetic attachment system in each of the first and second electronic devices. In one embodiment, the activating can be a result of a keyed magnetic interaction between the magnetic system and each of the magnetic attachment systems. In one embodiment, the keyed magnetic interaction can take the form of an interaction between magnetic fields having properties based upon an arrangement of magnetic elements in the magnetic system and the magnetic attachment systems in the first and second electronic devices. 
     In one embodiment, the magnetic attachment unit can be formed of a bendable yet sturdy material. In this way, a portion of the magnetic attachment unit magnetically attached to the first electronic device can be bent in such a way that a display on the first electronic device is presented to a user at a comfortable viewing angle of about 70°-75° while the second electronic device remains flat on a supporting surface such as a table. In this way, the second electronic device can display an input (such as a virtual keyboard, GUI, and so on) that can be used to input data to the cooperative system. In one embodiment, the first electronic device can present visual content in accordance with the current state of the cooperative system. 
     For example, the second electronic device can present a virtual keyboard that can be used to provide input commands and/or data and such to the cooperative system by the magnetic attachment of the first and second electronic devices. In the case where the magnetic attachment unit is associated with a math tutorial, for example, information provided to the first and second electronic devices can cause a display of the first electronic device to present subject matter (math equations to solve, problems, etc.) for which the student can interact by using the virtual keyboard presented by a display of the second electronic device. 
     These and other embodiments are discussed below with reference to  FIGS. 1-35 . However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be construed as limiting. For the remainder of this discussion, a first and second object each suitably configured to magnetically attach to each other in accordance with the described embodiments will be described. It should be noted, however, that any number and type of suitably configured objects can be magnetically attached to each other in a precise and repeatable manner. In particular, for simplicity and clarity, for the remainder of this discussion, the first object is presumed to take the form of an electronic device and in particular a handheld electronic device. 
       FIG. 1  is a simplified block diagram of article  10  and electronic device  12  that can be releasably attached to each other in a desired and repeatable manner. More specifically, article  10  and electronic device  12  can attach to each other at a pre-determined position and relative orientation without external intervention and without the use of mechanical fasteners. Article  10  and electronic device  12  can remain attached to each other if and until a releasing force is applied that overcomes the engagement between them. In some cases, however, it can be desirable to detach article  10  and electronic device  12  serially (along the lines of a zipper) in which case, a releasing force can be applied that can undo the engagement between article  10  and electronic device  12  about one attachment component at a time. For example, an attachment component can include a suitably matched pair of magnetic elements, one in article  10  and a second in electronic device  12 . 
     Electronic device  12  can take many forms. For example, electronic device  12  can take the form of a portable electronic device. In some examples, the portable electronic device can include housing  15 . Housing  15  can enclose and provide support for components of the portable electronic device. Housing  15  can also provide support for at least a large and prominent display occupying a substantial portion of a front face of the portable electronic device. The display can be used to present visual content. The visual content can include still images, visual, textual data, as well as graphical data that can include icons used as part of a graphical user interface, or GUI. 
     In some cases, at least a portion of the display can be touch sensitive. By touch sensitive it is meant that during a touch event, an object (such as a finger, stylus, and so on) can be placed in contact with or in proximity to an upper surface of the display. The particulars of the touch event (location, pressure, duration, and so forth) can be used to provide information to the portable electronic device for processing. In some embodiments, in addition to or in place of information being provided to the portable electronic device, information can be provided by the portable electronic device in a tactile manner using, for example, haptic actuators. It should be appreciated however that this configuration is by way of example and not by way of limitation as the electronic device can be widely varied. In one example, the portable electronic device is a tablet computer such as, for example, the iPad™ manufactured by Apple Inc. of Cupertino, Calif. 
     Article  10  can be widely varied and can take many forms such as, for example, an accessory or accoutrement of electronic device  12 . As an accessory, article  10  can be configured as a cover, a stand, a dock, a hanger, an input/output device and so on. In a particularly useful form, article  10  can take the form of a protective cover that can include a member, such as a flap, that can be positioned over the display of the portable electronic device. Like the electronic device  12 , the article  10  can also include housing  17  that can enclose and provide support for components of the article  10 . 
     Either one or both of article  10  and electronic device  12  can include attachment features. For example, article  10  can include attachment system  13  and electronic device  12  can include corresponding attachment system  14 . Attachment system  13  can cooperate with corresponding attachment system  14  to attach article  10  and electronic device  12  in a releasable manner. When attached to each other, article  10  and electronic device  12  can operate as a single operating unit. On the other hand, in the detached mode, article  10  and electronic device  12  can act separately, and if desired, as two individual parts. Attachment systems  13  and  14  can be configured in such a way that article  10  and electronic device  12  can attach to each other in a desired and repeatable manner. In other words, attachment systems  13  and  14  can repeatedly align article  10  and electronic device  12  together such that they are consistently in a pre-determined position relative to one another. 
     The attachment features can be widely varied. The attachment can be provided by various types of couplings including mechanical, electrical, static, magnetic, frictional, and/or the like. In one embodiment, the attachment cannot be seen from the outside of the article and/or electronic device. For example, the article and device can not include external visible attachment features that adversely affect the look and feel or ornamental appearance (e.g., snaps, latches, etc.), but rather attachment features that cannot be seen from the outside of the article or device and thus do not affect the look and feel or ornamental appearance of the article or device. By way of example, the attachment features can be provided by attraction surfaces that do not disturb the external surfaces of the article or device. In one embodiment, at least a portion of the attachment features utilize magnetic attraction to provide some or all of the attaching force. 
     The attachment systems can include one or more attachment features. If multiple features are used, the manner in which they secure can be the same or different. For example, in one implementation, a first attachment feature utilizes a first attachment means while a second attachment feature utilizes a second attachment means that is different than the first attachment means. For example, the first attachment means can utilize a friction coupling while the second attachment means can utilize magnetism. In another implementation, a first attachment feature utilizes a first attachment means while a second attachment feature utilizes the same or similar attachment means. For example, the first and second attachment means can be provided by magnets. Although, the attachment means can be similar it should be appreciated that the configuration of the features can be different depending on the needs of the system. Further, any number and configuration of attachment means can be used. 
     In the illustrated embodiment, the attachment systems  13  and  14  each include at least a first set of corresponding attachment features  13   a / 14   a  and a second set of corresponding attachment features  13   b / 14   b . Attachment feature  13   a  can cooperate with corresponding attachment feature  14   a  to attach article  10  and electronic device in a releasable manner. In one particular implementation this is accomplished with magnetic attraction. Further, attachment feature  13   b  can cooperate with corresponding attachment feature  14   b  to further attach article  10  and electronic device in a releasable manner. In one particular implementation this is accomplished with magnetic attraction. By way of example, attachment features  13   a / 14   a  can be provided at a first location while attachment features  13   b / 14   b  can be provided at a second location. 
     In a specific example, attachment feature  14   a  can, in cooperation with attachment feature  13   a , secure electronic device  12  to article  10 . In another example, attachment feature  13   b  can secure article  10  to the electronic device  12  using attachment feature  14   b . It should be noted that the attachment systems  13  and  14  of this example can be separate or they can cooperate together to produce the attachment. If they cooperate, attachment features  14   a  and  14   b  correspond to or mate with one or more attachment features  13   a  and  13   b . In any case, the attachment features in any of these examples can be accomplished through mechanical, static, suction, magnetic attachment and/or the like. 
     The placement of the attachment systems and the attachment features within the attachment systems can be widely varied. Regarding electronic device  12 , attachment system  14  can be placed on front, back, top, bottom, and/or sides. Attachment features  14   a  and  14   b  can be placed any location within attachment system  14 . Accordingly, attachment features  14   a  and  14   b  can be placed anywhere relative to the housing and/or the display. In one example, the attachment features  14   a  and  14   b  can provide engagement along one or more of the sides of the housing (e.g., top, bottom, left, right). In another example, attachment features  14   a  and  14   b  can provide engagement at the back of electronic device  12 . In yet another example, attachment features  14   a  and  14   b  can provide engagement at the front (e.g., where, if present, a display is located) of electronic device  12 . In some cases, a combination of attachment features can be located at different regions of electronic device  12  as for example at the sides and front. In one embodiment, attachment system  14  including attachment features  14   a  and  14   b  do not disturb the surfaces of electronic device  12 . Similarly, attachment system  13  and in particular attachment features  13   a  and  13   b  do not disturb the surfaces of article  10 . 
     In accordance with one embodiment, the attachment features can include magnetic elements. The magnetic elements can be configured to help in positioning article  10  relative to electronic device  12  into a mating arrangement. The magnetic elements can further help to secure article  10  and electronic device  12  into a mating engagement. It should be noted that the engagement of article  10  and electronic device  12  can be reversed by the application of an appropriate releasing force that allows article  10  and electronic device  12  to separate back into individual objects. However, the magnetic elements can permit the article  10  and electronic device  12  to subsequently resume the mating engagement without the requirement of fasteners of any sort, mechanical or otherwise. In this way, the magnetic elements provide a repeatable and consistent engagement between article  10  and electronic device  12 . 
     Article  10  and electronic device  12  can further include components  16  and  18  respectively. Components  16  and  18  typically depend on the configuration of article  10  and electronic device  12  and can, for example, be mechanical or structural components used to provide support or they can be operational/functional components that can provide a specific set of operations/functions. The components can be dedicated to their respective devices or they may be configured for coupling with aspects of the corresponding article or device (e.g., wired or wireless). Examples of structural components can include frames, walls, fasteners, stiffeners, movement mechanisms (hinge), etc. Examples of operational components can include processors, memory, batteries, antennas, circuitry, sensors, display, inputs, and so on. Depending on their desired configuration, the components can be external (i.e., exposed at the surface) and/or internal (e.g., embedded within housing). 
       FIGS. 2A and 2B  are simplified perspective views of article  20  that can be releasably attached to electronic device  22  via a magnetic attachment system, in accordance with one described embodiment. Article  20  and electronic device  22  can generally correspond to those discussed with regards to  FIG. 1 . In one embodiment, the magnetic attachment system can be embodied as magnetic surface  24  (shown by broken lines or shading) and more particularly as magnetic surface  24  at the sides of electronic device  22 . Magnetic surface  24  can provide a magnetic field that can cooperate with a corresponding attachment feature in article  20  when placed in proximity to one another. The magnetic field can establish a net magnetic attractive force that can pull article  20  and electronic device  22  together into the mating engagement along engagement surface  26  as shown in  FIG. 2B . 
     In other words, the magnetic field provided by magnetic surface  24  can have properties such that the net magnetic attractive force between article  20  and electronic device  22  is substantially perpendicular to engagement surface  26 . Moreover, the magnetic field can result in the net magnetic attractive force between article  20  and electronic device  22  being applied uniformly along engagement surface  26 . In order to release article  20  and electronic device  22 , a releasing force can be applied to the two conjoined objects in order to overcome a net magnetic attractive force provided by the magnetic attachment system. 
     It also should be appreciated that although only one side wall is shown, in some cases different sidewalls and possibly a combination of sidewalls may be used depending on the needs of the attachment interface. It should be noted that the use of magnetic attachment precludes the need for mechanical attachments such as fasteners. Moreover, the lack of mechanical attachments and the uniformity of the overall magnetic attractive force can leave the surfaces of article  20  and electronic device  22  undisturbed helping to create an appearance of oneness by in which article  20  and electronic device  22  can appear as a single, unified entity. The uniformity in appearance can improve the overall aesthetic appeal of both article  20  and electronic device  22 . 
     In one embodiment, a magnetic surface can be created by embedding magnetically attractable elements in the form of the magnetic attachment feature within the sidewalls of electronic device  22  and/or article  20 . That is, the magnetically attractable elements can be disposed within article  20  and electronic device  22  as for example within the housing of electronic device  22 . In this configuration, the housing can be formed of non-magnetic material such as plastic or non-ferrous metal such as aluminum. In this way, magnetic force lines can be configured to work through the walls of the housing. The magnetic attachment features do not disturb the physical appearance of the external surfaces of article  20  and electronic device  22 . The magnetically attractable elements in article  20  and electronic device  22  can be arranged to produce magnetic fields that can cooperate with each other to generate a magnetic attractive force that attaches article  20  and electronic device  22  together in the mating engagement. The magnetic attractive force being configured to generate a magnetic attraction force normal to engagement surface  26  between electronic device  22  and article  20 . 
     The magnetic attractive force between corresponding magnetic elements in article  20  and electronic device  22  can also be uniformly applied along engagement surface  26 . The uniformity of the overall magnetic attractive force along engagement surface  26  can be a result of the uniformity of the separation distance between corresponding magnetic elements in article  20  and electronic device  22 . The uniformity can also be a result of the consistency of magnetic flux density between corresponding magnetic elements in article  20  and electronic device  22 . The uniformity of net magnetic attachment can be facilitated by the surfaces of article  20  and electronic device  22  each forming a well matched fit to each other. For example, one surface can be flat or have a concave geometry whereas the other surface can have a matching conforming convex geometry. In this way, by fitting tightly together, a separation distance between each of the corresponding magnetic elements in article  20  and electronic device  22  can be reduced to a minimum. The conformity of surface shapes can also enhance the overall look and feel of article  20  and electronic device  22  by reducing or eliminating the appearance of a seam at engagement surface  26 . This seamless quality can provide an illusion of a single entity when article  20  and electronic device  22  are attached to each other. 
     In addition to enhancing the overall look and feel, the consistency of the separation distance between the magnetic elements can render the attachment force between article  20  and electronic device  22  uniform along engagement surface  26 . In this way, the engagement force can be uniformly distributed across engagement surface  26  preventing buckling, weak spots, and so on that might otherwise affect the overall integrity of the engagement between article  20  and electronic device  22 . 
       FIGS. 3A and 3B  are simplified perspective views of article  20  that can take the form of electronic device  30  that can be directly and releasably attached to electronic device  32  via a magnetic attachment system in accordance with one described embodiment. In one embodiment, the magnetic attachment system can be embodied as magnetic surface  34  (shown by broken lines or shading) and more particularly as magnetic surface  34  at the sides of electronic device  32 . Magnetic surface  34  can provide a magnetic field that can cooperate with a corresponding attachment feature in electronic device  30  when placed in proximity to one another. The magnetic field can establish a net magnetic attractive force that can pull electronic device  30  and electronic device  32  together into the mating engagement along engagement surface  36  to form cooperating system  38  as shown in  FIG. 3B . 
       FIGS. 4A and 4B  are simplified perspective views of article  40  that can be releasably attached to electronic device  42  via magnetic attachment unit  44  and corresponding magnetic system  46 . It should be noted that this particular embodiment is similar to the embodiment described in  FIGS. 2A, 2B  except that magnetic attachment unit  44  is used to magnetically attach article  40  and electronic device  42  that were previously attached to each other directly at their respective side walls. In this way, attachment system  46  can include a plurality of magnetic attachment features arranged to provide suitable magnetic attachment for article  40  and electronic device  42 , respectively. 
       FIG. 4B  shows article  40  and electronic device  42  magnetically attached to each to each other by way of magnetic attachment unit  44  at engagement surfaces  47   a  and  47   b  to form cooperating system  48 . As part of system  48 , electronic device  42  and article  40  can cooperate with each other to provide features not available by article  40  or electronic device  42  separately. For example, article  40  can take the form of a hanging apparatus, docking apparatus, mounting apparatus and so forth that can provide features to a user not available by electronic device  42  separately. In one embodiment, article  40  can take the form of a docking system that can be magnetically attached to electronic device  42  by way of magnetic attachment unit  44 . In one embodiment, the docking system can provide mechanical support for electronic device  42 . In one embodiment, the docking system can act as to provide information to electronic device  42 . In one embodiment, the information can be stored within a storage device embedded in magnetic attachment unit  44 . In one embodiment, the information can be received at article  40  (by a WiFi connection, for example) and passed by way of magnetic attachment unit  44  to electronic device  42 , and vice versa. 
     In one embodiment, article  40  can be used to hang electronic device  42 . For example, article  40  can include hooks, fasteners, and so forth that can be used to grasp another object for support. Article  40  can be used to provide support for electronic device  42 . For example, article  40  can take the form of an articulating support that can be magnetically attached to electronic device  42 . The articulating nature of article  40  can be used to present electronic device  42  at various angles and orientations. It should be noted that due to the releasable nature of the magnetic attachment between magnetic attachment unit  44  and article  40  can be easily detached when electronic device  42  is to be used and subsequently re-attached when desired. 
       FIGS. 5A and 5B  are simplified perspective views of article  40  in the form of electronic device  50  that can be releasably attached to an electronic device  52  via magnetic attachment unit  54 . This embodiment is similar to that shown in  FIGS. 4A and 4B  in that magnetic attachment unit  54  can include multiple magnetically attractable elements. For example, magnetic elements can be placed within magnetic attachment unit  54  in such a way to create magnetic surfaces  56   a  and  56   b  suitable for activating magnetic attachment systems in electronic devices  50  and  52 , respectively. For example, the activation of the magnetic attachment system in electronic device  52  can result in magnetic surface  58  being presented at the side wall of electronic device  52 . Magnetic surface  58  can be used to magnetically attach magnetic attachment unit  54  and electronic device  52  at engagement surface  60   a . In one embodiment, magnetic surface  56   b  can be created at an opposing side wall of magnetic attachment unit  54 . In much the same way as with electronic  54 , magnetic surface  56   b  can be used to activate a magnetic attachment system in electronic device  50  that creates a magnetic surface suitable for magnetically attaching magnetic attachment unit  54  to electronic device  50  at engagement surface  60   b  creating cooperating system  62  shown in  FIG. 5B . 
     It should be noted, however, that although side to side magnetic attachment between electronic devices  50  and  52  are shown, in some embodiments, magnetic surfaces can be located on bottom surfaces and/or top surfaces of electronic devices  50  and  52 . For example, magnetic elements of magnetic attachment unit  54  can be embedded behind top surface  64  of magnetic attachment unit  54  creating magnetic surface  66  for attaching to rear surfaces of electronic devices  50  or  52  forming a back to back arrangement. It should be noted that although not shown, additional magnetic elements can be embedded in a bottom surface of magnetic attachment unit  54 . 
       FIG. 5B  shows electronic device  50  and electronic device  52  magnetically attached to each to each other to form cooperating system  62 . In this arrangement, electronic device  52  and electronic device  50  can cooperate with each other to provide features not available by electronic device  50  or electronic device  52  separately. For example, electronic device  50  can receive information in the form of, for example, an input command from a user and/or input data from, for example, a sensor. Electronic device  50  can process the information in whole or in part and pass the processed information to electronic device  52  for further processing In this way, cooperating system  62  can process the information in a more efficient manner preserving computational resources that provides an enhanced user experience over that expected from either electronic device  50  or  52  acting separately. 
     Cooperating system  62  can be formed by placing magnetic attachment unit  54  and electronic devices  50  and  52  in proximity to each other such that magnetic surfaces  56   a  and  56   b  on the sides of magnetic attachment unit  54  activate magnetic attachment systems in electronic devices  52  and  50 , respectively. The activated magnetic systems, in turn, provide magnetic surfaces (such as magnetic surface  58 ) that interact with magnetic attachment unit  54  to create a net magnetic attractive force of sufficient magnitude and direction to maintain electronic device  50  and electronic device  52  in a mating engagement to form cooperating system  62 . 
     In one embodiment, magnetic attachment unit  54  can be formed of rigid material. In one embodiment, magnetic attachment unit  54  can be bendable. In one aspect, the bendable nature of magnetic attachment unit  54  can be used to provide a user with a user interface such as a keyboard and a display that can be presented as a visually comfortable angle such as 75°. 
     Although the purpose of the magnetic elements is similar, i.e., attach article to electronic device, attach electronic device to electronic device, it should be appreciated that these mechanisms can widely vary. In some cases, the magnetic fields may be configured differently. By way of example, the side mounted magnetic surface may provide a first magnetic force and the front facing magnetic surface may provide a second magnetic force that is different than the first magnetic force. This may be in part due to different holding requirements as well as different surface areas, i.e., available space, and its effect on internal components of the electronic device. In one example, the side mounted magnetic surface provides a greater holding force for securing the article (or electronic device) to the electronic device (i.e., it is the primary securing force) while the front facing magnetic surface is the secondary securing force. 
     In one example, magnetic attachment unit  54  includes multiple sections that are semi-rigid and bend relative to one another so as to make magnetic attachment unit movable and flexible. In one embodiment, magnetic attachment unit  54  can be folded into one or more different configurations, and in some cases can be held in these configurations using a magnetic system similar to what is described above. These and other embodiments will be described in greater detail below. Moreover, it should be appreciated that the described embodiments are not limited to that specifically described herein and other configurations can be used including for example as an accessory device used as a hanging apparatus, as a support mechanism for the electronic device to improve viewing the display and as a support mechanism for or inputting touch events at a touch sensitive portion of the display, and so on. 
     The electronic device and article can take many forms. For the remainder of this discussion, the electronic device is described in terms of a handheld portable computing device. Accordingly,  FIG. 6  shows a top perspective view of electronic device  100  in accordance with the described embodiments. Electronic device  100  can process data and more particularly media data such as audio, visual, images, etc. By way of example, electronic device  100  can generally correspond to a device that can perform as a smart phone, a music player, a game player, a visual player, a personal digital assistant (PDA), a tablet computer and the like. Electronic device  100  can also be hand held. With regards to being handheld, electronic device  100  can be held in one hand while being operated by the other hand (i.e., no reference surface such as a desktop is needed). Hence, electronic device  100  can be held in one hand while operational input commands can be provided by the other hand. The operational input commands can include operating a volume switch, a hold switch, or by providing inputs to a touch sensitive surface such as a touch sensitive display device or a touch pad. 
     Electronic device  100  can include housing  102 . In some embodiments, housing  102  can take the form of a single piece housing formed of any number of materials such as plastic or non-magnetic metal which can be forged, molded, or otherwise formed into a desired shape. In those cases where electronic device  100  has a metal housing and incorporates radio frequency (RF) based functionality, a portion of housing  102  can include radio transparent materials such as ceramic, or plastic. Housing  102  can be configured to enclose a number of internal components. For example, housing  102  can enclose and support various structural and electrical components (including integrated circuit chips) to provide computing operations for electronic device  100 . The integrated circuits can take the form of chips, chip sets, or modules any of which can be surface mounted to a printed circuit board, or PCB, or other support structure. For example, a main logic board (MLB) can have integrated circuits mounted thereon that can include at least a microprocessor, semi-conductor memory (such as FLASH), and various support circuits and so on. Housing  102  can include opening  104  for placing internal components and as necessary can be sized to accommodate display assembly for presenting visual content, the display assembly being covered and protected by protective layer  106 . In some cases, the display assembly can be touch sensitive allowing tactile inputs that can be used to provide control signals to electronic device  100 . In some cases, the display assembly may be a large prominent display area that covers a majority of the real estate on the front of the electronic device. 
     Electronic device  100  can include a magnetic attachment system that can be used to magnetically attach electronic device  100  to at least one other suitably configured object. 
     The magnetic attachment system can include a number of magnetic attachment features distributed within and in some cases connected to housing  102 . For example, the magnetic attachment system can include first magnetic attachment feature located in proximity to side wall  102   a  and a second magnetic attachment feature located beneath cover glass  106 . In one embodiment, the first magnetic attachment feature can operate in multiple states. For example, in an inactive state, the first magnetic attachment feature can provide first magnetic surface M1 at an exterior surface of side wall  102   a . First magnetic surface M1 can be represent a magnetic field that has little or no effect on magnetically sensitive devices placed at the exterior surface of side wall  102   a  and is also not suitable for magnetic attachment. In other words, magnetic surface M1 is consistent with magnetic flux density B at side wall  102  that satisfies Eq. (1):
 
 B≦B   threshold   Eq. (1)
 
where B threshold  represents a value of magnetic flux density B corresponding to a value of magnetic flux leakage at side wall  102   a  that does not facilitate magnetic attachment at side wall  102   a  and does not substantially affect a magnetically sensitive device at side wall  102   a.  
 
     In an active state, however, the first magnetic attachment feature can provide second magnetic surface M2 at the exterior surface of side wall  102  as shown in  FIG. 6B  in cross hatch. Magnetic surface M2 is consistent with facilitating magnetic attachment at the exterior surface of side wall  102  that satisfies Eq. (2):
 
 B&gt;B   threshold   Eq. (2).
 
     In one embodiment, an external magnetic field having appropriate magnetic properties can cause the first magnetic attachment system to transition from the inactive state to the active state. In this way, the magnetic surface expressed at side wall  102   a  can change from magnetic surface M1 (shown in  FIG. 6A ) to magnetic surface M2 (shown in  FIG. 6B ). The external magnetic field can be provided by a magnetic attachment feature external to electronic device  100  that cooperates with the first magnetic attachment feature causing the operating state of the first magnetic attachment feature to change from inactive to active. 
     The second magnetic attachment feature can aid in the magnetic attachment of another device to electronic device  100  by providing magnetic surface M3 that satisfies Eq. (2). In one embodiment, the second magnetic attachment feature operates has one operating state consistent with providing magnetic surface M3. 
     Although not expressly shown, it is understood that the various magnetic attachment features of the magnetic attachment system can be located at any appropriate location of housing  102 . For example, magnetic attachment features can be located at an interior bottom surface of housing  102  or along sides  102   c  and  102   d  of housing  102 . 
     As shown in  FIGS. 7A-7B  and referring back to the discussion above with regards to  FIGS. 5A-5B , magnetic attachment unit  54  can be used to magnetically attach electronic devices  100  and  120  to form cooperating system  130  at engagement surfaces  132   a  and  132   b . Cooperating system  130  can utilize resources from both electronic devices  100  and  120  singly or in combination. In one embodiment, electronic device  100  can present a virtual keyboard that can respond to a touch event by wirelessly sending corresponding information to electronic device  120 . Electronic device  120  can use the information to provide a response. For example, a user can select from a list of icons presented by electronic device  100  a particular media item, or items. An identification of the selected media item(s) can be forwarded (either wirelessly or by way of a wired connection) to electronic device  120 . In one embodiment, electronic device  120  can decode and present at least a portion of the selected media item. 
       FIGS. 8A-8C  show various embodiments of magnetic attachment unit  200  that can be used to magnetically attach electronic device  100  to an object having a suitably configured magnetic attachment system. The object can take the form of an accessory device. The object can take the form of an electronic device. In some cases, the accessory device can include electronic components that can communicate with electronic device  100 , and vice versa. In any case, magnetic attachment unit  200  as can include magnetic attachment features  202  and  204  connected together by way of flexible member  206 . In one embodiment, magnetic attachment features  202  and  204  can be fixedly attached to flexible member  206 . In one embodiment, magnetic attachment features  202  and  204  can be pivotally connected to flexible member  206  thereby providing additional degrees of freedom for magnetic attachment unit  200 . 
       FIG. 8A  shows a cross sectional side view magnetic attachment features  202  and  204  in accordance with the described embodiments. In this particular illustration, magnetic attachment features  202  and  204  are magnetically attached to a portion of housing  102  having a substantially flat surface. It should be noted, however, that housing  102  can have a curved shape in which case, the shape of various components of magnetic attachment features  202  and  204  described below can take on a shape that conforms to the shape of housing  102 . In this way, a separation distance between corresponding magnetic elements within housing  102  and magnetic attachment features  202  and  204  can be minimized thereby maximizing a net magnetic attractive force. 
     It should be noted that in the following description, magnetic attachment features  202  and  204  have substantially the same configuration. However, in some embodiments, magnetic attachment features  202  and  204  can differ somewhat in structure depending upon the nature and form of the objects being magnetically attached together. Therefore, for succinctness, magnetic attachment feature  202  will be described only. 
     Magnetic elements in electronic device  100  can magnetically interact with corresponding magnetic element  204 . In one embodiment, magnetic element  208  can have thickness of about 2 mm and have a shape that substantially conforms to that of housing  102 . The magnetic interaction between magnetic element  208  and those magnetic elements in electronic device  100  can create net magnetic attractive force consistent with a separation distance x sep  is about equal to the total of the thickness t of housing  102  and thickness “l” of label  210 . Thickness “l” can be on the order of about 0.2 mm. Label  210  can be used to protect the exterior surface of housing  102  against possible scratching and other cosmetic damage potentially caused by metal to metal contact between magnetic element  208  and housing  102 . Both label  210  and magnetic element  208  can each be shaped to conform to the shape of housing  102 . In this way, the distance between magnetic element  208  and the magnetic element in electronic device  100  can be reduced to about the thickness t of housing  102  and thickness l of label  210 . 
     Magnetic shunt  212  can be glued to and enclose that portion of magnetic element  208  facing away from housing  102 . Magnetic shunt  212  can be formed of magnetically active material such as steel or iron. The magnetically active material can redirect magnetic flux lines that would otherwise be directed away from magnetic elements in electronic device  100  towards housing  102  thereby increasing the total magnetic flux density B between magnetic attachment feature  202  and electronic device  100 . Magnetic shunt  212  can, in turn, be glued to housing  214  of magnetic attachment feature  202 . It should be noted, that in order to assure that only label  210  contacts housing  214  (to avoid metal to metal contact), label  210  is proud (i.e., protrudes) of housing  102  by about distance “d”. Nominally, distance d can be on the order of about 0.1 mm. 
       FIG. 8B  shows an embodiment of magnetic attachment feature  200  where magnetic attachment features  202  and  204  are coupled to rigid member  216 . As noted above, magnetic attachment features  202  and  204  can be fixedly connected to rigid member  216 . In one embodiment, magnetic attachment features  202  and  204  can be pivotally connected to rigid member  216 . 
       FIG. 8C  shows another embodiment of magnetic attachment unit in the form of magnetic attachment unit  220  where magnetic attachment features  202  and  204  are incorporated within connecting member  222  (that can be either rigid or flexible). In this configuration, there is no need for housing  214 . Therefore, only magnetic element  208 , label  210 , and shunt  212  are required. 
     The remainder of this discussion will describe particular embodiments of devices that can use the magnetic attachment system. In particular, electronic device  100  will henceforth be described in terms of a tablet computing device such as the iPad™ manufactured by Apple Inc. of Cupertino, Calif. 
     In one embodiment, accessory device  120  can be used to enhance the overall functionality of electronic device  100 . For example, accessory device  120  can be configured to act as a hanging apparatus. When magnetically attached to electronic device  100 , accessory device  120  can be used to hang electronic device  100 . In this way, electronic device  100  can be used as a display for presenting visual content such as art, movies, photos and so forth on a wall or suspended from a ceiling. As a hanging apparatus, accessory device  120  can be used to hang electronic device  100  from a wall or a ceiling. Electronic device  100  can be easily removed by simply exerting a releasing force sufficient to overcome the net magnetic attractive force F NET . Accessory device  120  can be left in place and be used to reattach electronic device  100  (or another device) at a later time. 
     In one embodiment, accessory device  120  can also take the form of a holding mechanism for attaching objects that are not by themselves equipped to magnetically attach to electronic device  100 . For example, accessory device  120  can be configured to carry a stylus or other such input device. The stylus can be used to provide inputs to the electronic device. In some cases, accessory device  120  can provide a signal to electronic device  100  indicating the presence of the stylus. The signal can cause electronic device  100  to enter into a stylus recognition state, for example. More particularly, when accessory device  120  is magnetically attached to electronic device  100 , electronic device  100  can activate a stylus input state in order to recognize stylus type inputs. When accessory device  120  is removed, electronic device  100  can de-activate the stylus input state. In this way, the stylus can be conveniently attached/detached to electronic device  100  when needed. 
     Accessory device  120  can take the form of a support that can be used to enhance the functionality of electronic device  100 . For example, accessory device  120  can be configured to act as a display stand on which a display of electronic device  100  can be viewed at a comfortable viewing angle such as 75°. In other words, when placed upon a horizontal surface such as a table or desk, accessory device  120  can support electronic device  100  in such a way that the visual content presented at the display can be viewed at about a viewing angle of approximately 75°. 
     Accessory device  120  can also take the form of a support that can be used to enhance the functionality of electronic device  100  in a keyboard state. In the keyboard state, accessory device  120  can be used to present a touch pad surface at an angle that is ergonomically friendly. In this way, input touch events can be applied (to a virtual keyboard, for example) at an angle that does not overtax a user&#39;s wrist, hands, arms, etc. 
       FIG. 9  illustrates an arrangement  300  formed by magnetically attaching tablet device  302  and tablet device  304  by way of flexible magnetic attachment unit  306  in an open configuration. Magnetic attachment unit  306  can include flexible connecting member  308  arranged to connect pivoting hinge assemblies  310  and  312  to each other, each of which are in turn magnetically connected to tablet device  304  and  302 , respectively. The hinge assemblies can provide one or more pivots to allow magnetic attachment unit  306  to fold over while magnetic attachment unit  306  is magnetically attached to devices  302  and  304 . 
     In one embodiment, hinge assembly  310  can include first hinge portion (also referred to as first end lug)  314  and a second hinge portion (or second end lug)  316  disposed opposite the first end lug. First end lug  314  can be rigidly connected to second end lug  316  by way of connecting rod (not shown) incorporated into connecting member  308  providing an additional pivoting axis. The connecting rod can be formed of metal or plastic strong enough to rigidly support tablet devices  302  and  304 . 
     Hinge span  318  can include magnetic elements. The magnetic elements can be arranged to magnetically attach hinge span  318  to a magnetic attachment feature having a matching arrangement of magnetic elements in tablet devices  302  and  304 . More specifically, the magnetic elements within hinge span  318  can activate a magnetic feature in tablet devices  302  and  304  rendering them capable of magnetically attaching to hinge span  318 . Hinge span  318  can be formed of magnetically inactive material such as plastic or non-magnetic metal such as aluminum. 
     Arrangement  300  can be referred to as a book in that each tablet device  302  and  304  can present visual information in a book like manner. For example, as shown in  FIG. 9 , in the open configuration, arrangement  300  can resemble an open book in which display  320  of tablet device  302  can function like a page in an open book (as can display  322  of tablet  304 ). In one embodiment, a user can “flip” pages by simply swiping a touch sensitive surface of tablet device  302  (or that of tablet device  304 ) to flip forward using, for example, a left to right page flipping gesture. On the other hand, in order to flip a page (or pages) backwards, the user can swipe a touch sensitive surface on either tablet device  302  or  304  using, for example, a right to left page flipping gesture. 
     In any case, in the book mode shown in  FIG. 9 , tablet devices  302  and  304  must communicate with each other in order to provide a reasonable approximation of a book and a manner in which a book presents information. This communication can take the form of a wireless communication between tablet devices  302  and  304 . 
       FIG. 10  shows arrangement  300  in a closed configuration in which tablet device  302  and  304  use the flexible nature of flexible connecting member  306  to fold atop one another. In one embodiment, magnetic elements beneath displays  320  and  322  can be arranged in such a way that prevents tablet devices  302  and  304  from touching each other. In one configuration, the magnetic elements can be arranged to interact in such a way as to create a net magnetic repulsion force between tablet device  302  and tablet device  304  preventing contact between them. In one embodiment, the magnetic elements can be arranged to create a net magnetic attractive force that can lock tablet device  302  and  304  together. In one embodiment, the magnetic elements can be arranged to provide little or no magnetic force in the closed configuration. 
       FIGS. 11A and 11B  shows tablet devices  302  and  304  magnetically attached to each other by way of magnetic attachment unit  330 . In one embodiment, magnetic attachment unit  330  can includes connecting member  332  formed of rigid portion  334  and  336  pivotally connected to each other by way of hinge (or clutch barrel)  338 . As shown in  FIG. 11A , tablet device  302  can be placed upon a flat supporting surface such as a table. Tablet device  304  can then be positioned in a vertical orientation relative to tablet device  302 . In this way, tablet device  304  can act as a display for presenting visual content. 
       FIG. 12A  shows tablet device  302  and  304  connected together by way of magnetic attachment unit  340 . As shown, magnetic attachment unit  340  does not include hinge assemblies  318  and is thus fixedly attached to tablet devices  302  and  304 . Magnetic attachment unit  340  can include rigid connecting members  342  pivotally connected to each other by way of clutch barrel, or hinge,  338 . In this way, as shown in  FIG. 12B , tablet device  302  can be placed upon a flat supporting surface such as a table and another electronic device (such as tablet  304 ) can be positioned to act as a display. As can be seen in  FIGS. 12B and 12C , tablet device  304  can be replaced by electronic device  100  that is not necessarily a tablet device. For example, electronic device  100  can take the form of a simple display capable of being magnetically attached to magnetic attachment unit  340 . In one embodiment, magnetic attachment unit  340  can actually be formed as part of electronic device  100 . In this way, magnetic attachment unit  340  can include only a single magnetic attachment feature suitable for magnetically attaching to tablet device  302 . 
     As shown in  FIG. 12C , support structure  350  can be used to provide additional support for the upraised electronic device, regardless of whether the upraised electronic device takes the form of electronic device  100  or tablet device  304 . 
       FIG. 13  shows magnetic attachment unit  220  magnetically attaching tablet devices  302  and  304  to form tablet array  360 . Accordingly, tablet device  302  and  304  can communicate with each other by way of a wireless connection. In one embodiment, the wireless connection can take the form of a WiFi wireless communication where tablet devices  302  and  304  communicate with each other directly. In one embodiment, tablet devices  302  and  304  can communicate with each other in part by way of an external circuit, such as a wireless router, server computer, and so on. In one embodiment, magnetic attachment unit  220  can provide communication resources to assist in the communication between tablet devices  302  and  304 . In one embodiment, magnetic attachment unit  220  can include processing as well as data storage resources that can be used to alter the operating state of either or both tablet devices  302  and  304 . For example, when magnetic attachment unit  220  includes a data storage device (such as a FLASH memory), data in the storage device can be transferred to either or both tablet device  302  and  304 . The transferred data can take the form of instructions that can be executed to alter the operating state of the respective tablet device. 
       FIG. 14A  shows a cross section of system  400  in accordance with an embodiment. System  400  can include tablet device  402  magnetically attached to cover assembly  404  by way of magnetic hinge assembly  406 . Cover assembly  404  can include segmented cover  408  pivotally attached to hinge assembly  404  at pivot  410 . Hinge assembly  406  can be magnetically attached to tablet device  402  by way of magnetic element  412  in hinge assembly  404  and magnetic attachment feature  414  in tablet device  402 . Intervening layer  416  can act to prevent direct metal to metal contact between hinge assembly  406  and housing  418  of tablet device  402 . 
     Cover assembly  404  can also include separate flap portion  420  pivotally attached to hinge assembly  406  at pivot  422 . In this way, segmented cover  408  and flap portion  420  can be rotated about their respective pivots separately as shown in  FIG. 14B  where segmented cover  408  has been folded into support structure  424 . Support structure  424  can be triangular in shape and be used to position tablet device  402  such that display  426  is presented at about an angle of 75°. 
     Flap portion  420  can be formed of flexible material such as fabric. In one embodiment, flap portion  420  can include various input devices. For example, as shown in  FIG. 15 , flap portion  420  can include keyboard  430 . Keyboard  430  can be in communication with tablet device  402  using, for example, a wired connection. In one embodiment, keyboard  430  can be in wireless communication with tablet device  402 . Accordingly, a user can pass information to tablet device  402  by pressing various input keys of fabric keyboard  430 . 
     It should be noted that flap portion  420  can be configured to include any suitable type of input device. For example, in one embodiment shown in  FIG. 16 , flap portion  420  can take the form of input pad  440 . Input pad  440  can be sensitive to touch events such as those provided by a stylus, pen, pencil, or even a human appendage such as a finger. Still further as shown in  FIG. 17 , flap portion  420  can include touch pad  450  that can be used to provide information to tablet device  402  by a user touching touch pad  450  in a prescribed manner. 
       FIGS. 18A-18D  show magnetic docking station  500  in accordance with the described embodiments. Magnetic docking station  500  can include support  502  and base portion  504 . Base portion  504  can include magnetic elements  506  arranged to activate magnetic attachment feature in electronic device  100 . Therefore, placing of electronic device  100  into slot  508  of base portion  504  can result in magnetic elements  506  activating the magnetic attachment feature in electronic device  100 . The activation can cause a net attractive magnetic force between magnetic elements  506  and electronic device  100  strong enough to secure electronic device  100  to docking station  500 . In one embodiment shown in  FIG. 17B , electronic device  100  can take the form of tablet device  302 . In one embodiment, docking station  500  can provide electrical power to electronic device  100 . In one embodiment, docking station  500  and electronic device  100  can communicate with each other wirelessly by way of a suitable wireless communication protocol such as WiFi, BlueTooth, and so forth. In one embodiment, docking station  500  can include docking port(s) that provide a wired communication channel between electronic device  100  and another electronic device connected to docking station  500  or in some cases an input device such as a keyboard, keypad, touch pad, etc. In the embodiment shown in  FIGS. 18A-18D , docking station  500  is fixed in that electronic device  100  is presented at a substantially fixed angle and orientation with respect to a supporting surface, such as a table or desk on which an input device such as a keyboard can be located. 
     However, as shown in  FIG. 19A , docking station  600  can be pivot about pivot point  602 . In this way, electronic device  100  can be presented in any number of angles with respect to the supporting surface. Pivoting docking station  600  can include base portion  604  pivotally connected by way of pivot  602  to support  606 . In one embodiment, magnetic elements  610  can activate magnetic attachment feature  612  in electronic device  100  to magnetically couple electronic device  100  to pivoting docking station  600 . In one embodiment, magnetic elements  610  can be included in base portion  604 .  FIG. 19B  shows an embodiment where electronic device  100  takes the form of tablet device  302 .  FIG. 19C  shows articulating docking station  650  in accordance with an embodiment of the invention. 
       FIGS. 20A-20D  show various hanging accessories  700  that can be magnetically attached to tablet device  302  in accordance with the described embodiments. It should be noted that as shown, the hanging accessories each are formed to include magnetic elements arranged to activate the magnetic attachment feature included in tablet device  302 . This integrated arrangement can reduce the number of components required. In one embodiment, however, the hanging accessories can be magnetically attached to tablet device  302  using the magnetic attachment unit described above. In any case, the various hanging accessories can be used to hang or otherwise suspend tablet device  302  from any suitable surface. For example,  FIGS. 20A and 20B  show variations of hanging accessory  700  well suited for suspending tablet device  302  from a vertical wall. For example, hook accessory  702  and suction cup accessory  704  can be used to hang tablet device  302  from a vertical wall such as in an office cubicle in the case of hook accessory  702  and a refrigerator door, chalkboard, or whiteboard in the case of suction cup accessory  704  shown in  FIG. 20B . 
       FIGS. 20C and 20D  show embodiments of hanging accessory  700  that can allow a user to carry tablet device  302  about. For example, fixed handle accessory  706  can facilitate a user holding tablet device  302  firmly in one hand whereas strap accessory  708  can allow the user to carry tablet device  302  about in a more free flowing manner. 
       FIGS. 20E and 20F  show an embodiment of hanging accessory  700  that can be used to hang electronic device  100  from a vertical surface unsuitable for hooks or other grasping accessories. Such surfaces include whiteboards, black boards, smooth metal surfaces, wood surfaces, and so forth. Accordingly, hanging accessory  710  can include support  712  to which is attached suction cups  714  (or equivalent) that can be used to removably adhere hanging accessory  710  to the above said surfaces. Hanging accessory  710  also includes base portion  716  that includes magnetic elements  718  used to activate the magnetic attachment feature  720  in electronic device  100 .  FIG. 20E  shows an embodiment whereby electronic device  100  takes the form of tablet device  302  attached to whiteboard  722 . 
       FIGS. 21A-21B  show additional embodiments of hanging accessory  700  that can extend the usefulness and the range of applications for which tablet device  302  can be used. For example,  FIG. 21A  shows tablet device  302  mounted to a headrest of an automobile, for example, using clasp  712  that conforms to the shape of the headrest. In some embodiment, clasp  712  can be somewhat flexible in order to accommodate a variety of shapes and sizes of headrests. In another example,  FIG. 21B  shows clasp  714  that can be used to hang tablet device  302  from an airplane seat, for example, It should be noted that in both cases, tablet device  302  and be magnetically attached to both clasp  712  and  714  by way of magnetic elements embedded in base portions  716  and  718 , respectively. In one embodiment, base portions  716  and  718  can be pivotally connected to clasps  712  and  714  in order to provide the viewer with an adjustable viewing angle. 
     In addition to hanging, or otherwise mounting, as shown in  FIG. 22A , tablet device  302 , mounting accessory  720  can be used to mount tablet device directly to an automobile dashboard, for example. In one embodiment, mounting accessory  720  can be secured to the dashboard  724  and can include magnetic elements that can be used to activate the magnetic attachment feature included in tablet device  302 . In addition to mechanically securing tablet device  302  to the dashboard, mounting accessory  720  can be used to port power to tablet device  302 , provide a connection to other electronic devices within the vehicle, and so on. For example, when tablet device  302  can wirelessly transmit audio and in some cases video data to an appropriate receiver circuit. In this way, media data can be ported from tablet device  302 . In one embodiment, tablet device  302  can be used in conjunction with other electronic services available to the vehicle. For example, GPS based navigation can be displayed on tablet device  302 , traffic warnings can be posted, vehicle information (gas level, charge level, etc.) can be posted and so on. In one embodiment, user input can be provided to tablet device  302 . The user input can be used to alter an operating characteristic of the vehicle, media, and so forth.  FIG. 22B  shows mounting accessory  720  can be used to mount tablet device  302  to exercise equipment such as tread mill  722 . 
       FIGS. 23A-23H  show embodiments of tablet device  302  magnetically attached to various peripheral devices  800 . For example,  FIG. 23A  shows camera  802  magnetically attached to tablet device  302 . Camera  802  can operate in conjunction with or separately from image capture resources included in tablet device  302 .  FIG. 23B  shows stylus holder  804  with stylus  806 . In one embodiment, the operation of tablet device  302  can change to a stylus recognition mode when stylus holder  804  (or the presence of stylus  806 ). In the stylus recognition mode, the operation of tablet device  302  can be such that movements of stylus  806  upon display  808  can be recognized and acted upon by tablet device  302 . 
       FIG. 23C  shows card swipe  810  magnetically attached to tablet device  302 . In this arrangement, a user can swipe a magnetically coded card, for example, and the information being readily made available for processing by tablet device  302 .  FIG. 23D  shows RF antenna assembly  812  that can be used to supplement RF reception and transmission of tablet device  302 . 
       FIG. 23E  shows memory module  814  magnetically attached to tablet device  302  arranged to provide additional memory resources to tablet device  302 .  FIG. 23F  shows keyboard  816  magnetically attached to tablet device  302 . Keyboard  816  can communicate with tablet device  302  wirelessly or by a wired connection. 
       FIG. 23G  shows game controller  818  magnetically connected to tablet device  302 . In one embodiment, game controller  818  can provide information to tablet device  302 . The information can include the game to be played, historical game information, player information and identification and so forth.  FIG. 23H  shows audio output module  820  having speakers  822  for broadcasting audio content provided by tablet device  302 . 
       FIG. 24  shows travel case  900  that can be used to store and transport tablet device  902 . Travel case  900  can include magnetic elements  904  arranged to activate magnetic attachment feature  906  in tablet device  902 . In one embodiment, travel case  900  can have a clam shell type arrangement whereby cover  908  can, in a closed configuration, enclose tablet device  902  within a cavity formed by cover  908  and base  910 . In one embodiment, tablet device  902  can be manually released by grasping and removing tablet device  902 . In one embodiment, travel case  900  can include a releasing mechanism that can overcome the magnetic attraction between magnetic elements  904  and the magnetic attachment feature  906  in tablet device  902 . In one embodiment, the releasing mechanism can be mechanical in nature. In one embodiment, the releasing mechanism can be electromechanical in nature in which an electromagnetic element in travel case  900  can be energized to overcome the magnetic attraction between magnetic elements  904  and magnetic attachment feature  906 . 
       FIGS. 25A and 25B  show representative magnetic attraction between magnetic elements  920  in object  922  and magnetic attachment feature  924  in an electronic device that can take the form of tablet device  926 . As shown in  FIG. 25A , magnetic elements  920  can include at least one electromagnetic element that can be used to provide electromotive force. The electromotive force can be used to overcome net magnetic attractive force F net  between magnetic elements  920  and magnetic attachment feature  922 . The electromotive force can cause object  922  to separate from the electronic device without the use of hands or other mechanical mechanism. The electromagnetic element can be remotely activated or can be activated using the electronic device. For example, when the electronic device takes the form of tablet device  930 , home button  932  can be pressed thereby causing the activation of the electromagnetic element resulting in the magnetic attraction between magnetic attachment feature  922  and magnetic elements  920  being overcome allowing tablet device  930  to be removed from travel case  900 . 
       FIGS. 26A-26C  graphically illustrate a mechanism whereby a magnetically sensitive circuit, such as a Hall Effect sensor can be used to alter an operating state of an electronic device. In particular,  FIG. 26A  shows tablet device  1000  in an OFF operating state. Tablet device  1000  can include a magnetically sensitive circuit, such as Hall Effect sensor  1002 . In one embodiment, tablet device  1000  can also include light sensitive device  1004 . In one embodiment, light sensitive device  1004  can take the form of an ambient light sensor (ALS). In one embodiment, light sensitive device  1004  can take the form of an image capture device such as a camera. It should be noted that light sensitive device  1004  can also take the form of any combination of devices incorporated which, for example, a sensor board that can includes both an ambient light sensor and a camera that can operate independent or in cooperation with each other. 
     In one embodiment, an operating state of tablet device  1000  can be altered by an external magnetic field H. In one embodiment, external magnetic field H can transient in nature by which it is meant that external magnetic field H can vary in time and/or magnetic field strength. In one situation, external magnetic field H can be generated by a magnetic element, such as magnetic ring  1006 , that generates a substantially non-transient magnetic field that is nonetheless transient as perceived by magnetically sensitive device  1002 . For example, by moving magnetic ring  1006  from left to right as shown in  FIGS. 26A-26C , Hall Effect sensor  1002  can detect the external magnetic field H as being transient in nature in that the strength of external magnetic field H starts at an initial value and increases in value as magnetic ring  1006  approaches Hall Effect sensor  1002  and then decreases again as magnetic ring  1006  moves away from Hall Effect sensor  1002 . The detection of the transient external magnetic field H provided by the movement of magnetic ring  1006  can result in Hall Effect sensor  1006  providing a signal to tablet device  1000 . The signal can be interpreted by tablet device  1000  to change from a current operating state (such as OFF) to another operating state (such as ON) as shown in  FIG. 26C . In one embodiment, the change in state of tablet device  1000  can be binary in nature in that by passing ring  1006  by Hall Effect sensor  1002  a second time, the signal provided by Hall Effect sensor  1002  can be interpreted by tablet device  1000  to change the current operating state from ON to OFF. In one embodiment, additional sensors (such as ALS, ambient light sensor or camera  1004 ) can be used in conjunction (or singly) to provide additional inputs that can be used to alter the operating state of tablet device  1000  in additional ways. 
       FIGS. 27A and 27B  shows a representative embodiment of hands-free detaching of magnetically coupled objects. In particular,  FIG. 27A  shows magnetically attached configuration  1100  where first magnetic attachment feature  1102  is magnetically attached to second magnetic attachment feature  1104 . In one embodiment first magnetic attachment feature  1102  can include element  1106  that is responsive to an externally applied voltage (or current), provided by, for example, voltage (or current) source  1108  to generate a magnetic field having polarity P1 so long as the externally applied voltage (or current) is available. 
     In one embodiment, when no voltage or current is applied, element  1106  provides substantially little or no magnetic flux and is therefore not capable of supporting a magnetic attachment based solely upon any intrinsic magnetic field. In one embodiment second magnetic attachment feature  1104  can include magnetic element  1110  aligned with and in proximity to magnetic element  1106  when first magnetic attachment feature  1102  is placed in proximity to second magnetic attachment feature  1104 . In one embodiment, magnetic element  1110  can have an intrinsic polarity P1 that is the same as the polarity of element  1106  when the external current I or voltage V is applied as shown in  FIG. 27B . In this way, a net repulsive magnetic force in the form of ejection force F eject  can be generated between element  1106  and magnetic element  1110  during the duration of the availability of voltage V or current I. In this way, by properly adjusting the size, distance, magnetic properties, and electromagnetic properties, first magnetic attachment feature  1102  and second magnetic attachment feature  1104  can be detached from each other. For example, in t magnetically attached state  1100 , applying voltage V or current I to magnetic element  1106  can create ejection force F eject  that forces first magnetic attachment feature  1102  and second magnetic attachment feature  1104  to separate in separated state of  1112  automatically or at least without the need for manually detachment. 
       FIGS. 28A and 28B  shows first magnetic attachment feature  1200  having magnetic window  1202  capable of selectively controlling magnetic flux leakage B at exterior surface  1204  of housing  1206 . In one embodiment, magnetic window  1202  can be formed of channel  1208  arranged to accommodate magnetic fluid  1210 . In one embodiment, magnetic fluid  1210  can take the form of a ferrofluid that is a liquid which becomes strongly magnetized in the presence of a magnetic field. Ferrofluids are colloidal in nature formed of a liquid having nanoscale ferromagnetic, or ferrimagnetic, particles suspended in a carrier fluid-usually an organic solvent or water. Each tiny particle is thoroughly coated with a surfactant to inhibit clumping. Large ferromagnetic particles can be ripped out of the homogeneous colloidal mixture, forming a separate clump of magnetic dust when exposed to strong magnetic fields. The magnetic attraction of nanoparticles is weak enough that the surfactant&#39;s van de Waals repulsion is sufficient to prevent magnetic clumping. Ferrofluids usually do not retain magnetization in the absence of an externally applied field. 
     Therefore, in the inactive state (i.e., Eq. (1) is satisfied), magnetic attachment feature  1200  can include magnetic elements  1212  embedded in or in close proximity to housing  1206  where magnetic fluid  1210  interacts with magnetic field generated by magnetic elements  1212 . The magnetic nature of magnetic fluid  1210  prevents any flux leakage at exterior surface  1204  of housing  1206  thus providing a boundary condition required to satisfy Eq. (1). In this way, there is no requirement for moving magnetic elements  1212  in order to provide magnetic surface M1 at exterior surface  1204 . In one embodiment, magnetic window  1202  can also include reservoirs  1214  (either one or a plurality) that provide sufficient volume to accommodate magnetic fluid  1210  as shown in  FIG. 28B . 
     In one embodiment, second magnetic attachment feature  1216  can include a mechanism that can cause magnetic fluid  1210  to migrate out of channel  1208  into one or both reservoirs  1214  to expose magnetic elements  1212 . By exposing magnetic elements  1212 , magnetic surface M2 can be provided satisfying Eq. (2). In one embodiment, the mechanism used to migrate magnetic fluid  1210  can take the form of magnets  1218  having strong enough magnetic field strength to overcome the attraction of magnetic elements  1212 . In this way, the placement of second magnetic attachment feature  1216  in proximity to first magnetic attachment feature  1200  can cause magnetic window  1202  to go from a closed state (consistent with Eq. (1)) to an open state (consistent with Eq. (2)). 
       FIGS. 29A and 29B  shows first magnetic attachment feature  1300  having a retaining mechanism in the form of retaining magnets  1302 . By providing magnets  1302 , valuable space can be preserved. Since the strength and size of magnets  1302  can be well defined, the size and strength of activating magnets  1304  in second magnetic attachment feature  1306  can also be well defined. For example, in order to activate first magnetic attachment feature (i.e., satisfying Eq. (2)), magnets  1308  must move from inactive position X1 (magnetically attached to magnets  1302 ) to active position X2. This can be accomplished by placing activating magnets  1304  in proximity to magnets  1308 . In one embodiment, the intrinsic magnetic strength of magnets  1304  and  1308  can be adjusted to overcome the magnetic attraction between magnets  1302  and magnets  1308  causing magnets  1308  to detach from magnets  1302  and move towards magnets  1304  creating magnetic surface M2 in the process (i.e., satisfying Eq. (2)). 
       FIGS. 30A and 30B  shows an embodiment of first magnetic attachment feature  1300  having channels  1310  sized to accommodate moving magnets  1308  and retaining magnets  1302 . In one embodiment, moving magnets  1308  can travel within channel  1310  smoothly and with little resistance due to the presence of a lubricant (not shown) between moving magnets  1308  and interior surfaces of channels  1310 . 
       FIGS. 31A-31C  show another embodiment of first magnetic attachment feature  1300  shown in  FIGS. 30A-30B  arranged to provide information based upon an attachment configuration. In one embodiment, all or at least some of magnets  1302  are electrically isolated from chassis ground formed by the metal of housing  1206 . In one embodiment, all or at least some of magnets  1302  can be coupled to a sensing circuit arranged to sense if magnet  1308  is attached to magnet  1302 . In those cases where the sensing circuit senses that magnet  1308  is attached to magnet  1302 , then a first logic value (“0” or “1”, whichever is deemed appropriate) can be provided. Conversely, when the sensing circuit senses that magnet  1308  is not attached to magnet  1302 , then a second logic value (“1” or “0) different from the first logic value can be provided. In one embodiment, information in the form of the first and second logic values can be used to identify a magnetic attachment state. In one embodiment, the attachment state can identify an object magnetically attached (see Table 1 shown in  FIG. 32 ). In one embodiment, the attachment information corresponding to the attachment state can be used to alter an operating state of an electronic device, such as tablet device  1000 . For example, using the information provided by Table 1, if the sense circuit senses data {1, 0, 0, 0, 0, 1} corresponding to a stylus, then tablet device  1000  can alter a current operating state to one consistent with sensing a stylus upon a touch screen or display. 
       FIGS. 32A and 32B  show specific embodiments of first attachment feature  1300  shown in  FIGS. 31A-31C . In one embodiment, retaining magnet  1302  can be electrically isolated from housing  102  and include electrical contact  1320  electrically connected by way of line  1322  to the sense circuit. As can be seen, when retaining magnet  1302  is not attached to moving magnet  1308 , there is no electrical path between the sensing circuit and chassis ground, and therefore substantially no current flows corresponding to the second logic state. On the other hand, as shown in  FIG. 32B , when moving magnet  1308  is in contact with retaining magnet  1302  and more particularly electrical contact  1320 , current path  1326  is provided allowing current I to flow to/from chassis ground.  FIG. 33  shows a table of representative operating magnetic codes and operating states. 
       FIG. 34  is a block diagram of an arrangement  1600  of functional modules utilized by an electronic device. The electronic device can, for example, be tablet device  1500 . The arrangement  1600  includes an electronic device  1602  that is able to output media for a user of the portable media device but also store and retrieve data with respect to data storage  1604 . The arrangement  1600  also includes a graphical user interface (GUI) manager  1606 . The GUI manager  1606  operates to control information being provided to and displayed on a display device. The arrangement  1600  also includes a communication module  1608  that facilitates communication between the portable media device and an accessory device. Still further, the arrangement  1600  includes an accessory manager  1610  that operates to authenticate and acquire data from an accessory device that can be coupled to the portable media device. 
       FIG. 35  is a block diagram of an electronic device  1650  suitable for use with the described embodiments. The electronic device  1650  illustrates circuitry of a representative computing device. The electronic device  1650  includes a processor  1652  that pertains to a microprocessor or controller for controlling the overall operation of the electronic device  1650 . The electronic device  1650  stores media data pertaining to media items in a file system  1654  and a cache  1656 . The file system  1654  is, typically, a storage disk or a plurality of disks. The file system  1654  typically provides high capacity storage capability for the electronic device  1650 . However, since the access time to the file system  1654  is relatively slow, the electronic device  1650  can also include a cache  1656 . The cache  1656  is, for example, Random-Access Memory (RAM) provided by semiconductor memory. The relative access time to the cache  1656  is substantially shorter than for the file system  1654 . However, the cache  1656  does not have the large storage capacity of the file system  1654 . Further, the file system  1654 , when active, consumes more power than does the cache  1656 . The power consumption is often a concern when the electronic device  1650  is a portable media device that is powered by a battery  1674 . The electronic device  1650  can also include a RAM  1670  and a Read-Only Memory (ROM)  1672 . The ROM  1672  can store programs, utilities or processes to be executed in a non-volatile manner. The RAM  1670  provides volatile data storage, such as for the cache  1656 . 
     The electronic device  1650  also includes a user input device  1658  that allows a user of the electronic device  1650  to interact with the electronic device  1650 . For example, the user input device  1658  can take a variety of forms, such as a button, keypad, dial, touch screen, audio input interface, visual/image capture input interface, input in the form of sensor data, etc. Still further, the electronic device  1650  includes a display  1660  (screen display) that can be controlled by the processor  1652  to display information to the user. A data bus  1666  can facilitate data transfer between at least the file system  1654 , the cache  1656 , the processor  1652 , and the CODEC  1663 . 
     In one embodiment, the electronic device  1650  serves to store a plurality of media items (e.g., songs, podcasts, etc.) in the file system  1654 . When a user desires to have the electronic device play a particular media item, a list of available media items is displayed on the display  1660 . Then, using the user input device  1658 , a user can select one of the available media items. The processor  1652 , upon receiving a selection of a particular media item, supplies the media data (e.g., audio file) for the particular media item to a coder/decoder (CODEC)  1663 . The CODEC  1663  then produces analog output signals for a speaker  1664 . The speaker  1664  can be a speaker internal to the electronic device  1650  or external to the electronic device  1650 . For example, headphones or earphones that connect to the electronic device  1650  would be considered an external speaker. 
     The electronic device  1650  also includes a network/bus interface  1661  that couples to a data link  1662 . The data link  1662  allows the electronic device  1650  to couple to a host computer or to accessory devices. The data link  1662  can be provided over a wired connection or a wireless connection. In the case of a wireless connection, the network/bus interface  1661  can include a wireless transceiver. The media items (media assets) can pertain to one or more different types of media content. In one embodiment, the media items are audio tracks (e.g., songs, audio books, and podcasts). In another embodiment, the media items are images (e.g., photos). However, in other embodiments, the media items can be any combination of audio, graphical or visual content. Sensor  1676  can take the form of circuitry for detecting any number of stimuli. For example, sensor  1676  can include a Hall Effect sensor responsive to external magnetic field, an audio sensor, a light sensor such as a photometer, and so on. 
     The various aspects, embodiments, implementations or features of the described embodiments can be used separately or in any combination. Various aspects of the described embodiments can be implemented by software, hardware or a combination of hardware and software. The described embodiments can also be embodied as computer readable code on a non-transitory computer readable medium. The computer readable medium is defined as any data storage device that can store data which can thereafter be read by a computer system. Examples of the computer readable medium include read-only memory, random-access memory, CD-ROMs, DVDs, magnetic tape, and optical data storage devices. The computer readable medium can also be distributed over network-coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. They are not target to be exhaustive or to limit the embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings. 
     The advantages of the embodiments described are numerous. Different aspects, embodiments or implementations can yield one or more of the following advantages. Many features and advantages of the present embodiments are apparent from the written description and, thus, it is intended by the appended claims to cover all such features and advantages of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, the embodiments should not be limited to the exact construction and operation as illustrated and described. Hence, all suitable modifications and equivalents can be resorted to as falling within the scope of the invention.

Metadata:
Filing Date: 20150213
Publication Date: 20161115
Grant Date: 20161115
Priority Date: 20110131
Inventors: CORBIN SEAN S.
LAUDER ANDREW D.
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F1/1654", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1656", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1643", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1647", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B1/3822", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1656", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60R2011/0057", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1643", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1654", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1673", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C13/002", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C13/002", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0482", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1652", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C13/002", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C2200/15", "inventive": false, "first": false, "tree": "[]"}, {"code": "A63B71/0622", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1643", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1654", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60R11/0252", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1681", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1647", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1647", "inventive": true, "first": false, "tree": "[]"}, {"code": "B60R2011/0017", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0202", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1632", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "A63B2071/0658", "inventive": false, "first": false, "tree": "[]"}, {"code": "B60R2011/0005", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C2200/15", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1652", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1632", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/1446", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F2200/1631", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1652", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/003", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C11/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1632", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C11/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1656", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1652", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C2200/15", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1632", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C2011/003", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C11/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1647", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C13/002", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1643", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1654", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 45615068