Patent Publication Number: US-2012026098-A1

Title: Portable electronic device having tabletop mode

Description:
FIELD OF TECHNOLOGY 
     The present disclosure relates to portable electronic devices. 
     BACKGROUND 
     Mobile electronic devices, including handheld electronic communication devices, have gained widespread use and may provide a variety of functions including, for example, telephonic, electronic text messaging, personal information manager (PIM) application functions, mobile web browsing, and audio and video playback, among other things. Such devices are frequently intended for handheld use and ease of portability. In certain environments, it is desirable to use a mobile device without the user having to physically hold the device, such as when the mobile device is laying on a flat surface or in a cradle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present disclosure will now be described, by way of example only, with reference to the attached Figures, wherein: 
         FIG. 1  is a simplified block diagram of components including internal components of a handheld electronic communication device according to an example embodiment; 
         FIG. 2  is a front view of an example of a portable electronic device in a vertical, portrait orientation; 
         FIG. 3A  is a side view of the portable electronic device of  FIG. 2  in a vertical, portrait orientation; 
         FIG. 3B  is a side view of the portable electronic device of  FIG. 2  in a inclined, portrait orientation; 
         FIG. 3C  is a side view of the portable electronic device of  FIG. 2  in a horizontal, portrait orientation; 
         FIG. 3D  is a bottom end view of the portable electronic device of  FIG. 2  in a horizontal, portrait orientation; 
         FIG. 4  is a front view of the portable electronic device of  FIG. 2  in a horizontal, portrait orientation; 
         FIG. 5  is a front view of the portable electronic device of  FIG. 2  in a horizontal, landscape orientation; 
         FIG. 6  is a flow chart of example actions performed on the portable electronic device of  FIG. 1 ; and 
         FIG. 7  is a front view of a further example of a portable electronic device in a vertical, portrait orientation. 
     
    
    
     DETAILED DESCRIPTION 
     According to one example is a method implemented on a portable electronic device for facilitating user input, the portable electronic device having a display screen on a front face thereof, a side edge substantially orthogonal to the front face, and a side input button located on the side edge having an associated input function. The method includes: monitoring for a predetermined trigger condition; and upon detecting the predetermined trigger condition, enabling a user input interface accessible on the front face of the device to provide the input function associated with the side input button. 
     According to one example there is provided a portable electronic device that has a housing having a display screen on a front face thereof and a side edge substantially orthogonal to the front face. A side input button is located on the side edge and having an associated input function. The device includes a processor operatively coupled to the display screen and the side input button, the processor being configured for: monitoring for a predetermined trigger condition; and upon detecting the predetermined trigger condition, enabling a user input interface accessible on the front face of the device to provide the input function associated with the side input button. 
     For simplicity and clarity of illustration, reference numerals may be repeated among the figures to indicate corresponding or analogous elements. Numerous details are set forth to provide an understanding of the example embodiments described herein. The embodiments may be practiced without these details. In other instances, well-known methods, procedures, and components have not been described in detail to avoid obscuring the example embodiments described. The description is not to be considered as limited to the scope of the example embodiments described herein. 
     The disclosure generally relates to an electronic device, which is a portable electronic device in the examples described herein. Examples of portable electronic devices include mobile, or handheld, wireless communication devices such as pagers, cellular phones, cellular smart-phones, wireless organizers, personal digital assistants, wirelessly enabled notebook computers, and so forth. The portable electronic device may also be a portable electronic device without wireless communication capabilities, such as a handheld electronic game device, digital photograph album, digital camera, or other device. 
     A block diagram of an example of a portable electronic device  100  is shown in  FIG. 1 . The portable electronic device  100  includes multiple components, such as a processor  102  that controls the overall operation of the portable electronic device  100 . Communication functions, including data and voice communications, are performed through a communication subsystem  104 . Data received by the portable electronic device  100  is decompressed and decrypted by a decoder  106 . The communication subsystem  104  receives messages from and sends messages to a wireless network  150 . The wireless network  150  may be any type of wireless network, including, but not limited to, data wireless networks, voice wireless networks, and networks that support both voice and data communications. A power source  142 , such as one or more rechargeable batteries or a port to an external power supply, powers the portable electronic device  100 . 
     The processor  102  interacts with other components, such as Random Access Memory (RAM)  108 , memory  110 , a display screen  112  (such as a liquid crystal display (LCD)) with a touch-sensitive overlay  114  operably connected to an electronic controller  116  that together comprise a touch-sensitive display  118 , one or more keys or buttons  120 , a navigation device  122 , one or more auxiliary input/output (I/O) subsystems  124 , a data port  126 , a speaker  128 , a microphone  130 , short-range communications subsystem  132 , and other device subsystems  134 . User-interaction with a graphical user interface (GUI) is performed through the touch-sensitive overlay  114 . The processor  102  interacts with the touch-sensitive overlay  114  via the electronic controller  116 . Information, such as text, characters, symbols, images, icons, and other items that may be displayed or rendered on a portable electronic device, is displayed on the touch-sensitive display  118  via the processor  102 . The processor  102  interacts with an attitude sensor such as an accelerometer  136  that may be utilized to detect direction of gravitational forces or gravity-induced reaction forces. 
     The navigation device  122  may be a depressible (or clickable) joystick such as a depressible optical joystick, a depressible trackball, a depressible scroll wheel, or a depressible touch-sensitive trackpad or touchpad.  FIG. 2  shows a mobile electronic device  100  having a navigation device  122  in the form of a depressible optical joystick. The auxiliary I/O subsystems  124  may include other input devices such as a keyboard or keypad. 
     To identify a subscriber for network access, the portable electronic device  100  uses a Subscriber Identity Module or a Removable User Identity Module (SIM/RUIM) card  138  for communication with a network, such as the wireless network  150 . Alternatively, user identification information may be programmed into memory  110 . 
     The portable electronic device  100  includes an operating system  146  and software applications or programs  148  that are executed by the processor  102  and are typically stored in a persistent, updatable store such as the memory  110 . Additional applications or programs  148  may be loaded onto the portable electronic device  100  through the wireless network  150 , the auxiliary I/O subsystem  124 , the data port  126 , the short-range communications subsystem  132 , or any other suitable subsystem  134 . 
     A received signal such as a text message, an e-mail message, or web page download is processed by the communication subsystem  104  and input to the processor  102 . The processor  102  processes the received signal for output to the display screen  112  and/or to the auxiliary I/O subsystem  124 . A subscriber may generate data items, for example e-mail messages, which may be transmitted over the wireless network  150  through the communication subsystem  104 . For voice communications, the overall operation of the portable electronic device  100  is similar. The speaker  128  outputs audible information converted from electrical signals, and the microphone  130  converts audible information into electrical signals for processing. 
       FIG. 2  shows a front view of an example of a portable electronic device  100  in a vertical, portrait orientation. The portable electronic device  100  of  FIG. 2  is configured for use as a handheld device and includes a housing  200  that houses internal components including internal components shown in  FIG. 1  and frames the touch-sensitive display  118  such that the touch-sensitive display  118  is exposed on a front face  202  of the portable electronic device for user-interaction therewith when the portable electronic device  100  is in use. It will be appreciated that the touch-sensitive display  118  may include any suitable number of user-selectable features rendered thereon, for example, in the form of virtual or soft buttons for user-selection of, for example, applications, options, or keys of a keyboard for user entry of data during operation of the portable electronic device  100 . 
     The touch-sensitive display  118  may be any suitable touch-sensitive display, such as a capacitive, resistive, infrared, surface acoustic wave (SAW) touch-sensitive display, strain gauge, optical imaging, dispersive signal technology, acoustic pulse recognition, and so forth, as known in the art. A capacitive touch-sensitive display includes a capacitive touch-sensitive overlay  114 . The overlay  114  may be an assembly of multiple layers in a stack including, for example, a substrate, a ground shield layer, a barrier layer, one or more capacitive touch sensor layers separated by a substrate or other barrier, and a cover. The capacitive touch sensor layers may be any suitable material, such as patterned indium tin oxide (ITO). 
     In one example, as shown in  FIG. 2 , buttons  120  include buttons represented individually by references  120 A,  120 B,  120 C,  120 D,  120 E,  120 F and  120 G. Buttons  120 A,  120 B,  120 C and  120 D are front buttons located below the touch-sensitive display  118  on the front face  202  of the portable electronic device  100 . Buttons  120 E,  120 F and  120 G are side buttons located on side edges of the portable electronic device  100 —in one example, button  120 E is located on a left side edge  204  of the portable electronic device  100 , and buttons  120 F and  120 G are located on a right side edge  206  of the portable electronic device  100 . The side edges  204 ,  206  of the device are substantially orthogonal to the front face  202 . More or fewer buttons  120  can be provided on the front face and side edges and in different locations than illustrated in  FIG. 2 . The buttons  120  generate corresponding input signals when activated. The buttons  120  may be constructed using any suitable button (or key) construction such as, for example, a dome-switch construction. The front buttons  120 A,  120 B,  120 C and  120 D are activated by applying pressure (for example, by a user&#39;s fingertip) towards the front face  202  of the portable electronic device  100 . The side buttons  120 E,  120 F,  120 G are activated by applying pressure (for example, by a user&#39;s fingertip) towards the side edges of the portable electronic device  100 . 
     In some examples, the actions performed by the device  100  in response to activation of respective buttons  120  are context-sensitive. The action performed depends on a context that the button was activated. The context may be, but is not limited to, a device state, application, screen context, selected item or function, or any combination thereof. The front buttons  120 A,  120 B,  120 C and  120 D, in the shown example, are an answer (or send) button  120 A, menu button  120 B, escape (or back) button  120 C, and a hang up (or end) button  120 D. The send/answer button  120 A may be used for answering an incoming voice call, invoking a menu for a phone application when there is no voice call in progress, or initiating an outbound voice phone call from the phone application when a phone number is selected in the phone application. The menu button  120 B may be used to invoke a context-sensitive menu comprising context-sensitive menu options. The escape/back button  120 C may be used to cancel a current action, reverses (e.g., “back up” or “go back”) through previous user interface screens or menus displayed on the touch-sensitive display  118 , or exit the current application or program  148 . The end/hang up button  120 D may be used to end a voice call in progress or hide the current application  148 . 
     In one example, the left side button  120 E is configured in some contexts to activate a “voice input” function on the device  100  in which voice inputs are converted to text—for example a voice dialing function or a voice command entry function. In some examples, left side button  120 E is configured to operate in some contexts as a “push-to-talk” key for device to device communications. In some examples, side buttons  120 F and  120 G are configured as volume control buttons for the device—for example activating upper side button  120 F raises an output volume, and activating lower side button  120 G lowers an output volume. Visual feedback, for example volume bars, may be provided on display  118  to indicate a relative volume setting when buttons  120 F or  120 G are activated. Other side buttons may be provided on the top, bottom, right or left side edges of the device housing  200  such as, for example, a camera button for opening and operating a camera function. 
     In examples described herein, the portable electronic device  100  is configurable to operate in a “tabletop mode” in which user input functionality that is normally provided by one or more of the side buttons  120 E,  120 F and  120 G is temporarily mapped to user input interfaces that are accessible from the front face  202  of the portable electronic device  100  on the occurrence of one or more predetermined trigger conditions. By way of example, the trigger conditions that cause the portable electronic device  100  to operate in tabletop mode could occur when the device  100  is substantially stationary with its front face  202  facing in a generally upwards or vertical direction such as when the device  100  is resting on a horizontal support surface or in a cradle. In some situations, side buttons  120 E,  120 F and  120 G may be difficult to activate when the device  100  is resting on a support surface or held in a cradle, and providing alternative user input interfaces that can be accessed on the front face of the device may enhance the user experience and assist in the usability of the device  100 , particularly for users who have limited or impaired control of their hands. 
     In at least some examples the tabletop functionality described herein is implemented by computer code that is part of the operating system  146  or one or more programs  148 . Such computer code is executed by processor  102  to cause the systems and subsystems of the portable electronic device  100  to operate in the manner described below. 
     In some examples, a configurable user profile option is provided on the portable device  100  to enable or disable the operation of the tabletop mode on the device. By way of example,  FIG. 2  illustrates an example of a user profile option interface displayed on screen  118  in which a user is presented with “Yes” or “No” options to enable tabletop mode. In the illustrated example, the “Yes” option is shown as highlighted by an on-screen selection indicator  208 . The “Yes” or “No” options could for example be selectable by touching screen  118  at the appropriate location or using navigation device  122  to select one of the two options. The selected option would then be saved as a user profile. In some examples the electronic device  100  may be configured to operate in tabletop mode by default. The following describes the operation of the portable electronic device  100  when operation of the device  100  in tabletop mode is enabled. 
     In the example of  FIG. 2 , the front face  202  of the portable electronic device is substantially rectangular, having a longitudinal or major axis as indicated by dashed line  212  that extends from a top side edge  216  to a bottom side edge  210 , and a minor axis  214  as indicated by dashed line  214  that extends from left side edge  204  to right side edge  206 . The major axis  212  and minor axis  214  are perpendicular to each other and substantially parallel to the display screen  118  that is provided on the front face  202  of the electronic device  100 . 
     In order to explain an example operation of portable electronic device  100  when tabletop mode is enabled, various viewing orientations of the device  100  will be described. In  FIG. 2 , a vertical reference axis is represented by line “V”, and the electronic device  100  is illustrated in an upright or vertical viewing position with its major axis  212  being parallel to vertical V.  FIGS. 3A to 3C  show right side views of the electronic device  100  as it moves from a vertical orientation to a horizontal orientation. In particular, similar to  FIG. 2 ,  FIG. 3A  shows a right side view of the electronic device  100  in a vertical viewing orientation.  FIG. 3B  shows a right side view of the electronic device  100  in an inclined viewing orientation with the front face  202  of the device  100  and its major axis  212  being rotated an acute angle A° relative to vertical V.  FIG. 3C  shows a right side view of the electronic device  100  in a horizontal viewing position, with the front face  202  of the device  202  facing directly vertically (with the device major axis  212  being positioned at A=90° relative to vertical V).  FIG. 3D  shows the bottom side edge  210  of the portable electronic device  100  in a horizontal viewing position, with the front face  202  of the device  100  facing vertically. In each of the  FIGS. 3A to 3D , the device minor axis  214  is substantially perpendicular to vertical V, as illustrated in  FIG. 3D  by angle B. 
     In an example embodiment, upon the occurrence of predetermined trigger conditions, the portable electronic device  100  automatically implements a tabletop mode in which alternative input options accessible from the front face  202  of the device  100  are provided for at least some of the side buttons  120 F,  120 G and  120 E. In this regard, referring to action set  600  in  FIG. 6 , in one example, the processor  102  is configured to monitor for the occurrence of one or more predetermined trigger conditions (Action  602 ). In one example, the trigger condition depends on the orientation of electronic device  100 . Based on orientation information received from accelerometer  136 , the processor is configured to determine when the portable electronic device  100  meets a predetermined orientation threshold that indicates a trigger condition that the device should operate in a tabletop mode. The orientation threshold could include one or more threshold parameters. For example, the processor  102  could be configured to trigger tabletop mode when the angles A and B ( FIGS. 3A-3D ) each fall within a respective predetermined threshold range for a predetermined time duration. By way of non-limiting example, the processor could be configured to determine when a duration D of more than three seconds passes while: (i) the angle A between major axis  212  and the vertical V is in the range of 85 to 95 degrees and (ii) the angle B between minor axis  214  and the vertical V is in the range of 85 to 95 degrees, then the orientation threshold to trigger tabletop viewing mode has been met. In one example embodiment, the threshold ranges for one or more of angle A, angle B and a threshold duration D are stored in memory  110  and may be user configurable—for example, as shown in  FIG. 2  orientation threshold parameters may be user definable in the user profile setup interface screen that allows the tabletop mode to be enabled and disabled. In the non-limiting user profile example illustrated on screen  118  in  FIG. 2 , the threshold range for angle A is set at 70 to 95 degrees, the threshold range for angle B is set at 85 to 95 degrees and the threshold for duration D is greater than 1.5 seconds. 
     As indicated in  FIG. 6 , when the trigger condition for triggering tabletop mode is detected, alternative inputs on the front face  202  of the portable electronic device  100  are enabled for side buttons  120 E,  120 F and  120 G (Action  604 ). In this regard,  FIG. 4  shows a front view of the portable electronic device  100  in a horizontal viewing position, such as may be the case if the device  100  was resting face up on a horizontal support surface with its front face  102  facing substantially vertical—in  FIG. 4 , the vertical V (not shown) is coming directly out of the image, and angles A and B are each 90 degrees. In the example shown in  FIG. 4 , the processor  102 , in response to the placement of the device  100  in a horizontal viewing orientation, has caused a user selectable input element in the form of virtual volume slider bar  402  to be temporarily displayed on touch screen  118 . The volume slider bar  402  includes a virtual slider button  404  that can be dragged up and down slider bar  402  in response to a user&#39;s touch in order to adjust an output volume of the portable electronic device  100 . Accordingly, the volume slider bar  402  provides the same functionality as volume up side button  120 F and volume down side button  120 G. Thus, the volume slider bar  402  provides an alternative user input interface for side buttons  120 F and  120 G that is directly accessible on the front face  202  of the device  100 . In some examples, the presentation of the volume slider bar  402  is context dependent in that in Action  604 , the processor  102  will cause the volume slider bar  402  to be displayed on screen  118  only if an application or program currently being executed requires volume control. For example, if the electronic device  100  is in a phone call session or being used as a media player when in tabletop mode, then the volume slider bar  402  is displayed—however, if during the time the electronic device  100  is in tabletop mode none of the programs currently executing on the device require volume control, then the volume slider bar  402  will not be displayed. 
     In the example shown in  FIG. 4 , as part of Action  604  implemented in response to the placement of the device  100  in a horizontal viewing orientation, the processor also causes a user selectable input element in the form of virtual or soft key  406  to be temporarily displayed on touch screen  118  while the device  100  is in tabletop mode. The soft key  406  can be activated by a user touch of the key&#39;s display location on screen  118 , and provides the same input functionality as side button  120 E. For example, where activation of side button  102 E is a hot key for voice activation that enables voice input of commands to a speech-to-text application on the device, activation of soft key  406  has the same effect in tabletop mode. Similarly, where side button  102 E is enabled as a “push-to-talk” button for a peer-to-peer communications application on the device  100 , the soft key  406  also provides push-to-talk functionality. As noted above, in some examples side buttons such as side button  102 E may be user programmable, in which case soft key  406  will be associated with whatever input function the side button  102 E is currently programmed to implement. 
     In some examples, one or more of the side input buttons  120 E,  120 F and  120 G may be temporarily disabled when their front face alternative input interfaces  402 ,  406  are operational during tabletop mode, however in some embodiments both the front face input interfaces and side buttons remain operational in tabletop mode. 
     Portable electronic devices are commonly configured to switch, depending on device orientation, between a portrait display mode in which a vertical axis of a displayed image is parallel to the major axis of the device display screen, and a landscape display mode in which the vertical axis of the displayed image is parallel to a minor axis of the device display screen.  FIGS. 2 and 4  both show a portrait-oriented image display on the portable electronic device  100 . However, when portable electronic device  100  is in a horizontal viewing orientation with its front face  202  facing in a vertical direction, the relative orientation of the device to the user in terms of portrait or landscape viewing is not readily determined. Accordingly, in one example, as part of Action  604 , the processor  102  is configured to display as one of the temporary tabletop mode user input interfaces a touch-selectable soft key  408  on the screen  118  that allows a user to toggle between a portrait display mode and a landscape display mode. In this regard, in  FIG. 4 , the soft key  408  is labeled “Land” to indicate that user selection of the key  408  will toggle to a landscape display mode as shown in  FIG. 5 . In  FIG. 5 , the soft key  408  is labeled “Port” to indicate that user selection of the key  408  will toggle to a portrait display mode as shown in  FIG. 4 . 
     In some example embodiments, one or more of the front face input interfaces  402 ,  406 ,  408  are only displayed for a time limited duration after the electronic device  100  enters tabletop mode. In some embodiments, such time duration is configurable as part of the user profile for the device  100 . 
     As indicated in Action  606  in  FIG. 6 , after the portable electronic device  100  enters tabletop mode, the processor  102  subsequently monitors for the occurrence of one or more trigger conditions to exit tabletop mode. The trigger conditions that would cause the device  100  to exit tabletop mode could be the removal of the same trigger conditions that caused the device to enter tabletop mode. For example, the processor  102  can monitor device orientation information from accelerometer  136  to determine when the device orientation falls outside of the orientation threshold that was previously used as a trigger in Action  602 , and exit tabletop mode at that time. As indicated in Action  608 , the processor  102  disables the alternative user input interfaces that were provided on entering tabletop mode—in the example of  FIGS. 4 and 5 , virtual slider bar  402  and soft keys  406  and  408  are removed from the screen  118  once the monitored device orientation indicates the device is no longer in a stationary, horizontal viewing orientation. In some examples, the orientation threshold used in Action  602  to trigger entry into tabletop mode can be different than the orientation threshold used to trigger exit from tabletop mode in Action  602 . 
     As suggested above, in various examples the orientation threshold used in Action  602  to trigger tabletop mode can be broader than just a straight face up horizontal orientation of the portable electronic device  100  on a horizontal support surface. By way of example, the orientation threshold used in Action  602  could be configured to cause tabletop mode to be automatically triggered when the portable electronic device remains in at least a predetermined inclination from the vertical V without being completely horizontal, such as shown in  FIG. 3B . Portable electronic device  100  may be maintained in an inclined state such as shown in  FIG. 3B  if it is resting on an inclined support surface or secured in a cradle for viewing, for example. 
     In some examples, positional information other than or in addition to information from accelerometer  136  can be used by the processor  102  as trigger conditions for entering or exiting tabletop mode. By way of example, auxiliary I/O systems  124  may include a proximity sensor  124 A such as a Hall Effect sensor or physical switch for detecting when the portable electronic device  100  is mounted to a cradle that supports the portable electronic device  100  in a viewing position, and such information used to indicate a trigger condition in Action  602  for entering tabletop mode. In some examples, alternative trigger conditions can be used to trigger entry into tabletop mode—for example, if the device orientations falls within a predetermined orientation threshold or the electronic device  100  is mounted to a cradle, then tabletop mode is entered. In some examples the alternative trigger conditions can be user defined—in the user profile screen on  FIG. 2 , the user is presented with a yes or no option for identifying a “cradle” condition as being a trigger condition in addition to the various orientation parameters. 
     In some examples, the trigger condition for entering tabletop mode can be a predetermined user input such that the user manually triggers tabletop mode rather than having tabletop mode automatically triggered based on device orientation or proximity to a cradle—for example activating a certain button  120  or combination of buttons  120  could act as a trigger condition for entering and exiting tabletop mode in some example configurations. 
       FIG. 7  illustrates a further example of a handheld portable electronic device  700  to which the features described herein can be applied. With the exception of differences that will be apparent from the Figures and the following description, the portable electronic device  700  is substantially identical in construction and operation to device  100  with the exception that the buttons  120  of device  700  includes an array of buttons  720  arranged to provide a keyboard on the front face  702  of the device, including for example a plurality of alphanumeric input keys and control keys such as alt button  722 . In some examples the display screen  118  of the device  700  is a non-touch screen display. 
     As with device  100 , device  700  is configured to, on the occurrence of one or more predetermined trigger conditions, operate in a tabletop mode in which the functionality of one or more of the side buttons  120 E,  120 F and  120 G is temporarily mapped to a user input interface accessible on the front face  702  of the device  700 . The trigger conditions can be the same as those described above, such as for example, orientation in a predetermined position for a predetermined duration, mounting in a cradle, or a predetermined user input entry through one or more buttons  120 . However, in configurations where the screen  118  is not a touch screen, the user input interface mapping that occurs in tabletop mode is implemented by temporarily associating the functions associated with side buttons  120 E,  120 F and  120 G to hard buttons  120  that are located on the front face  702  of the portable electronic device  700 . In some examples, as front face buttons  120  typically already have assigned functions, associating the functions associated with side buttons  120 E,  120 F and  120 G to hard buttons  120  will require that some front face buttons  120  be assigned multiple input functions and a further button be used to control the specific input function that is triggered when a button is activated. 
     For example, in one implementation when in tabletop mode the button  120 C may be mapped to perform its normal input function as an escape/back button when pressed on its own, but also be mapped to act as the volume-up input button (i.e. the input functional normally assigned to side button  120 F) when pressed in combination with alt button  722 . Similarly, in tabletop mode the button  120 D may be mapped to perform its normal input function as an end/hangup button when pressed on its own, but also be mapped to act as the volume-down input button (i.e. the input functional normally assigned to side button  120 G) when pressed in combination with alt button  722 . In such a configuration activating buttons  120 C and  120 D in combination with the alt button  722  on the front face  702  of the device allows a user to control the volume output by the device  700 . In some examples, visual feedback may be provided in the form of a volume level indicator  704  displayed on the screen  118 . In some examples, the input functionality assigned to voice input/push-to-talk button  120 E is mapped to answer/send button  120 A such that pressing answer/send button  120 A in combination with the alt button  722  provides the same input functionality as activating side button  120 E. As per Actions  606  and  608 , the temporary assignment of side button input functions to front buttons  120 A,  120 C and  120 D is disabled once the portable electronic device  700  detects conditions triggering an exit from tabletop mode. 
     Accordingly, examples described herein provide a portable electronic device in which input functionality that is normally assigned to buttons located on the side edges of the electronic device is assigned to one or more user input interfaces that are accessible from the front face of the portable electronic device on the occurrence of one or more predetermined trigger conditions. By way of example, in various implementations the trigger conditions could include, among other things, one or more of a predetermined orientation of the portable electronic device, proximity of the electronic device to a mounting cradle, or a predetermined user input. In some situations, the side buttons may be difficult to activate when the device  100  is in certain positions such as resting on a support surface or held in a cradle, and providing alternative user input interfaces that can be accessed on the front face of the device may enhance the user experience and assist in the usability of the device  100 , particularly for users who have limited or impaired control of their hands. 
     While the present disclosure is described primarily in terms of methods, the present disclosure is also directed to a portable electronic device configured to perform at least part of the methods. The portable electronic device may be configured using hardware modules, software modules, a combination of hardware and software modules, or any other suitable manner. The present disclosure is also directed to a pre-recorded storage device or computer-readable medium having computer-readable code stored thereon, the computer-readable code being executable by at least one processor of the portable electronic device for performing at least parts of the described methods. 
     The present disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects as being only illustrative and not restrictive. The present disclosure intends to cover and embrace all suitable changes in technology. The scope of the present disclosure is, therefore, described by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are intended to be embraced within their scope.