Abstract:
A mobile terminal includes: a memory configured to store display information for displaying a plurality of display objects in standard positions for a dominant hand; a display configured to display the plurality of display objects based on the display information; and a processor coupled to the memory and configured to: determine whether the dominant hand is holding the mobile terminal using a sensor, control the display to display the plurality of display objects in the standard positions when the dominant hand is determined as holding the mobile terminal, and control the display to display the plurality of display objects in symmetrical positions determined using a change in the standard positions when the dominant hand is determined as not holding the mobile terminal.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2013-241826 filed on Nov. 22, 2013, the entire contents of which are incorporated herein by reference. 
       FIELD 
       [0002]    The embodiments discussed herein are related to a user interface technology. 
       BACKGROUND 
       [0003]    In Patent Literature 1 and Patent Literature 2, it has been discussed that whether a user operates a mobile device that includes a touch panel with the left hand or right hand is determined and an operation object is displayed in a position in which the user operates the operation object easily. However, identification of the above-described position based on the left hand or right hand by which the operation object is operated has not been described in detail in Japanese Laid-open Patent Publication No. 2012-215945 and International Publication Pamphlet No. WO2009/031214. 
       SUMMARY 
       [0004]    According to an aspect of the invention, a mobile terminal includes: a memory configured to store display information for displaying a plurality of display objects in standard positions for a dominant hand; a display configured to display the plurality of display objects based on the display information; and a processor coupled to the memory and configured to: determine whether the dominant hand is holding the mobile terminal using a sensor, control the display to display the plurality of display objects in the standard positions when the dominant hand is determined as holding the mobile terminal, and control the display to display the plurality of display objects in symmetrical positions determined using a change in the standard positions when the dominant hand is determined as not holding the mobile terminal. 
         [0005]    The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims. 
         [0006]    It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0007]      FIG. 1  is a diagram illustrating a state in which a mobile terminal device is held by the right hand; 
           [0008]      FIG. 2  is a diagram illustrating a state in which the mobile terminal device is held by the left hand; 
           [0009]      FIG. 3  is a diagram illustrating an example of a posture angle of the mobile terminal device; 
           [0010]      FIG. 4  is a diagram illustrating an arrangement example of icons; 
           [0011]      FIG. 5  is a diagram illustrating an arrangement example of the icons; 
           [0012]      FIG. 6  is a diagram illustrating an arrangement example of the icons; 
           [0013]      FIG. 7  is a diagram illustrating an arrangement example of the icons; 
           [0014]      FIG. 8  is a diagram illustrating a hardware configuration example of the mobile terminal device; 
           [0015]      FIG. 9  is a diagram illustrating a module configuration example of the mobile terminal device; 
           [0016]      FIG. 10  is a diagram illustrating an example of an icon table; 
           [0017]      FIG. 11  is a diagram illustrating a flow of main processing; 
           [0018]      FIG. 12  is a diagram illustrating a flow of determination processing; 
           [0019]      FIG. 13  is a diagram illustrating a flow of first display processing; 
           [0020]      FIG. 14  is a diagram illustrating a flow of first detection processing; 
           [0021]      FIG. 15  is a diagram illustrating the size of the icon; 
           [0022]      FIG. 16  is a diagram illustrating a flow of second display processing; 
           [0023]      FIG. 17  is a diagram illustrating an example of the symmetrical position for the icon; 
           [0024]      FIG. 18  is a diagram illustrating an example of the symmetrical position for the icon; 
           [0025]      FIG. 19  is a diagram illustrating a flow of symmetrical position calculation processing; 
           [0026]      FIG. 20  is a diagram illustrating a flow of second detection processing; 
           [0027]      FIG. 21  is a diagram illustrating a flow of symmetrical range calculation processing; 
           [0028]      FIG. 22  is a diagram illustrating an example of a numeric keypad; 
           [0029]      FIG. 23  is a diagram illustrating an arrangement example of the numeric keypad; 
           [0030]      FIG. 24  is a diagram illustrating an arrangement example of the numeric keypad; 
           [0031]      FIG. 25  is a diagram illustrating an arrangement example of the numeric keypad; 
           [0032]      FIG. 26  is a diagram illustrating an arrangement example of the numeric keypad; 
           [0033]      FIG. 27  is a diagram illustrating an example of a display object table; and 
           [0034]      FIG. 28  is a flow of main processing in a second embodiment. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0035]    For example, when the mobile device is held by the opposite hand to the dominant hand, a range with which the thumb is overlapped is different from that of the dominant hand. Thus, when a regular operation is performed by a finger of the opposite hand, the appearance of the screen is different from that of the dominant hand, and how to move the finger also becomes unfamiliar for the user, thereby sometimes confusing the user. 
         [0036]    However, it is troublesome to set the layout of a screen display separately in order to improve the usability when the mobile device is held by the opposite hand to the dominant hand. 
         [0037]    An object of an embodiment is to provide similar usability for both of a case in which a mobile device is held by the right hand and a case in which the mobile device is held by the left hand. 
       First Embodiment 
       [0038]    In the embodiment, whether a mobile terminal device  101  is held by the left hand or right hand is distinguished. 
         [0039]      FIG. 1  illustrates a state in which the mobile terminal device  101  is held by the right hand. As illustrated in  FIG. 1 , in the case in which the mobile terminal device  101  is held by the right hand, the display screen is generally tilted inward. The arrow in  FIG. 1  indicates a state in which the mobile terminal device  101  is slightly rotated in the counterclockwise direction from the user&#39;s view. 
         [0040]      FIG. 2  illustrates a state in which the mobile terminal device  101  is held by the left hand. As illustrated in  FIG. 2 , in the case in which the mobile terminal device  101  is held by the left hand, the display screen is generally tilted inward. The arrow in  FIG. 2  indicates a state in which the mobile terminal device  101  is slightly rotated in the clockwise direction from the user&#39;s view. 
         [0041]    In the embodiment, whether the user holds the left hand or right hand is determined based on the posture angle of the mobile terminal device  101  by assuming that the mobile terminal device  101  is held as illustrated in  FIG. 1  or  2 . 
         [0042]    The posture angle of the mobile terminal device  101  is described below.  FIG. 3  illustrates an example of the posture angle of the mobile terminal device  101 . In  FIG. 3 , the axis in the longitudinal top direction is set as an X-axis. In addition, the axis in the right direction is set as a Y-axis. The axis from the front side to the back side is set as a Z-axis. As illustrated in  FIG. 3 , a rotation angle of the X-axis is referred to as a roll angle β. In addition, a rotation angle of the Y-axis is referred to as a pitch angle α. In addition, a rotation angle of the Z-axis is referred to as a yaw angle γ. A state in which the display screen faces in the upper direction horizontally is set as a reference state. In addition, in the reference state, the roll angle β and the pitch angle α are 0 degree. 
         [0043]    In the state illustrated in  FIG. 1 , the roll angle β is approximately −10 degrees. In the state illustrated in  FIG. 2 , the roll angle β is approximately +10 degrees. 
         [0044]    An arrangement example of icons is described below.  FIG. 4  is a diagram illustrating an arrangement example of icons, which is suitable when a right-handed user uses the mobile device with the right hand. As illustrated in  FIG. 4 , a display screen  401  is portrait oriented. A center line  403  is a line that is used to divide the portrait-oriented display screen  401  into left and right equally. In the example, an icon  405   a  that is represented by “A”, an icon  405   b  that is represented by “B”, an icon  405   c  that is represented by “C”, and an icon  405   d  that is represented by “D” are arranged. 
         [0045]    It is assumed that the arrangement of the icons  405  is set by the user. In the example, it is assumed that the user often touches the icon  405  with the thumb of a hand that holds the mobile terminal device  101 . 
         [0046]    The icon  405   a  is used to start up a program called “AAA”. The icon  405   b  is used to start up a program called “BBB”. The icon  405   c  is used to start up a program called “CCC”. The icon  405   d  is used to start up a program called “DDD”. 
         [0047]    In the example, the right-handed user uses the program “AAA” and the program “BBB” frequently, so that it is assumed that the icon  405   a  and the icon  405   b  are arranged in the vicinity of the lower right corner of the display screen  401 . When the icons are arranged as described above, the program “AAA” and the program “BBB” are started up easily. 
         [0048]    It is assumed that the user does not use the program “CCC” and the program “DDD” frequently, and the icon  405   c  and the icon  405   d  are arranged on the left side of the center line  403 . When the icons are arranged as described above, the program “CCC” and the program “DDD” are not started up easily, but the usage frequency of the programs is low, so that the usability is not reduced. 
         [0049]    Thus, when the mobile terminal device  101  is held by the right hand that is the dominant hand, the arrangement that is described above is desired. However, when the mobile terminal device  101  is held by the left hand that is opposite to the dominant hand, the arrangement that is described above reduces for the usability. 
         [0050]    In the embodiment, in order to improve the usability when the mobile device is held by the opposite hand to the dominant hand, the arrangement of the icons  405  is changed. 
         [0051]      FIG. 5  illustrates an arrangement example of the icons, which is suitable when the right-handed user uses the mobile device with the left hand. In  FIG. 5 , the positions of the icon  405   a  that is represented by “A”, the icon  405   b  that is represented by “B”, the icon  405   c  that is represented by “C”, and the icon  405   d  that is represented by “D” are changed. For example, the icons are changed to the symmetrical positions for the positions illustrated in  FIG. 4  using the center line  403  as a symmetry axis. As a result, the icon  405   a  and the icon  405   b  are arranged in the vicinity of the lower left corner of the display screen  401 . In addition, the icon  405   c  and the icon  405   d  are arranged on the right side of the center line  403 . 
         [0052]    Therefore, the program “AAA” and the program “BBB” that are frequently used are easily touched by the thumb of the left hand. The program “CCC” and the program “DDD” are not easily touched by the thumb of the left hand, but the usage frequency of the programs is low, so that the usability does is not reduced. 
         [0053]    Thus, when the mobile device is held by the opposite hand to the dominant hand, the positional relationship between the icons and the hand is similar to that of the dominant hand. That is, an icon that is arranged at a position that is easily touched by the right hand is moved to a position that is also easily touched by the left hand. An icon that is arranged at a position that is not easily touched by the right hand is moved to a position that is also not easily touched by the left hand. 
         [0054]    In addition, there is also an aspect in which the icon  405   c  and the icon  405   d  that are arranged at positions that are seldom covered by the thumb of the right hand when the mobile device is held by the right hand are moved to positions that are seldom covered by the thumb of the left hand when the mobile device is held by the left hand. 
         [0055]    In the above-described example, the case is described in which the display screen  401  is portrait oriented, but even in a case in which the display screen  401  is landscape oriented, arrangement of the icons is changed depending on the hand that holds the mobile device. 
         [0056]    A case is described below in which the display screen  401  is landscape oriented using  FIGS. 6 and 7 .  FIG. 6  illustrates an arrangement example of the icons, which is suitable when the right-handed user uses the mobile device by the right hand. A center line  601  is a line that is used to divide the landscape oriented display screen  401  into left and right equally. 
         [0057]    The icon  405   a  that is represented by “A” and the icon  405   c  that is represented by “C” are arranged in the rightmost column, and the icon  405   b  that is represented by “B” and the icon  405   d  that is represented by “D” are arranged in the second rightmost column. The icons  405  are arranged on the right side as described above are easily touched by the thumb of the right hand. 
         [0058]      FIG. 7  illustrates an arrangement example of the icons, which is suitable when the right-handed user uses the mobile device by the left hand. In  FIG. 7 , the positions of the icon  405   a  that is represented by “A”, the icon  405   b  that is represented by “B”, the icon  405   c  that is represented by “C”, and the icon  405   d  that is represented by “D” are changed. For example, the icons are moved to the symmetrical positions for the positions illustrated in  FIG. 6  using the center line  601  as a symmetry axis. As a result, the icon  405   a  that is represented by “A” and the icon  405   c  that is represented by “C” are arranged in the leftmost column, and the icon  405   b  that is represented by “B” and the icon  405   d  that is represented by “D” are arranged in the second leftmost column. The icons  405  that are arranged on the left side as described above are easily touched by the thumb of the left hand. 
         [0059]    As described above, in the embodiment, whether the mobile terminal device  101  is held by the right hand or left hand is determined, and the arrangement of the icons is changed based on the determination result. The outline of the embodiment is as described above. 
         [0060]    A hardware configuration of the mobile terminal device  101  is described below.  FIG. 8  illustrates a hardware configuration example of the mobile terminal device  101 . The mobile terminal device  101  includes a bus  801 , a random access memory (RAM)  803 , a speaker  805 , a liquid crystal display (LCD)  807 , a touch pad  809 , a microphone  811 , a NAND memory  813 , a communication central processing unit (CPU)  815 , an application CPU  817 , a short-range communication device  819 , a global positioning system (GPS) device  821 , a wireless local area network (LAN) device  823 , a digital signal processor (DSP)  825 , an image signal processor (ISP)  827 , a camera  829 , a sub-processor  831 , a geomagnetic sensor  833 , a gyro sensor  835 , and an acceleration sensor  837 . 
         [0061]    From among the configuration elements, the RAM  803 , the speaker  805 , the LCD  807 , the touch pad  809 , the microphone  811 , the NAND memory  813 , the communication CPU  815 , the application CPU  817 , the short-range communication device  819 , the GPS device  821 , the wireless LAN device  823 , the DSP  825 , the ISP  827 , and the camera  829  are connected to each other through the bus  801 . 
         [0062]    The RAM  803  stores, for example, a program and data. The speaker  805  outputs audio. 
         [0063]    The touch pad  809  is, for example, a panel-like sensor that is arranged on a display screen of the LCD  807 , and accepts an instruction through a touch operation. The LCD  807  displays, for example, various screens through applications. For example, the LCD  807  and the touch pad  809  are integrated so as to be used as a touch panel. Through a touch operation to the touch pad  809 , a touch event occurs. 
         [0064]    To the microphone  811 , audio is input. The NAND memory  813  is a flash memory of a non-volatile storage element. The NAND memory  813  stores, for example, a program and data. The communication CPU  815  executes calculation processing that is related to communication processing. The application CPU  817  is, for example, a calculation device that executes an application program. The short-range communication device  819  is a device that controls short-range communication. The GPS device  821  is a device that measures the position of the mobile terminal device. The wireless LAN device  823  is a device that controls communication of a wireless LAN. The DSP  825  is a processor that executes digital signal processing. The ISP  827  is a processor that executes image processing. The camera  829  is a device that captures an image. 
         [0065]    In addition, the application CPU  817  is connected to the sub-processor  831 . The sub-processor  831  is connected to the geomagnetic sensor  833 , the gyro sensor  835 , and the acceleration sensor  837 . The sub-processor  831  controls the geomagnetic sensor  833 , the gyro sensor  835 , and the acceleration sensor  837 . The geomagnetic sensor  833  is a device that detects the orientation of geomagnetism and calculates the azimuth direction. The gyro sensor  835  is a device that detects a posture angular velocity. The acceleration sensor  837  is a device that measures acceleration. The geomagnetic sensor  833  and the gyro sensor  835  measure the above-described posture angle as well. 
         [0066]    In the example, the application CPU  817  obtains the measurement results of the geomagnetic sensor  833 , the gyro sensor  835 , and the acceleration sensor  837  through the sub-processor  831 , but the application CPU  817  may obtain the measurement results of the geomagnetic sensor  833 , the gyro sensor  835 , and the acceleration sensor  837  directly. 
         [0067]    The mobile terminal device  101  may be, for example, a game console, a controller, an electronic clock, an electronic dictionary, or the like, in addition to a mobile phone terminal device (including a feature phone and a smartphone). The hardware configuration of the mobile terminal device  101  is as described above. 
         [0068]    A module configuration of the mobile terminal device  101  is described below.  FIG. 9  illustrates a module configuration example of the mobile terminal device  101 . The mobile terminal device  101  includes a dominant hand storage unit  901 , a determination unit  903 , a display object data storage unit  905 , a display processing unit  907 , a detection unit  909 , and an execution unit  911 . 
         [0069]    The dominant hand storage unit  901 , the determination unit  903 , the display object data storage unit  905 , the display processing unit  907 , the detection unit  909 , and the execution unit  911  are obtained, for example, by the hardware resources illustrated in  FIG. 8 . In addition, a part or all of pieces of processing of the modules of the determination unit  903 , the display processing unit  907 , the detection unit  909 , and the execution unit  911  may be achieved by sequentially executing programs that have been loaded into the RAM  803  by the application CPU  817  or the sub-processor  831 . 
         [0070]    The dominant hand storage unit  901  stores data that is used to identify the dominant hand of the user. For example, the data that is used to identify the dominant hand of the user is registered to the dominant hand storage unit  901 . The determination unit  903  determines whether the hand that holds the mobile terminal device  101  is the right hand or the left hand. The display object data storage unit  905  stores data that is related to a display object. In the example, the display object data storage unit  905  stores an icon table. 
         [0071]      FIG. 10  illustrates an example of the icon table. Each icon includes a record. The record includes a field that is used to set an icon ID, a field that is used to set a portrait standard position, a field that is used to set a landscape standard position, and a field that is used to set a program name. 
         [0072]    The icon ID is an identifier that is used to identify an icon. The portrait standard position is data that is used to identify the display position of the icon in the display screen  401  when it is assumed that the display screen  401  is portrait oriented and the mobile terminal device  101  is held by the dominant hand. In the example, the portrait standard position indicates coordinates at the upper left corner of the icon when the X-axis is set in the right direction, and the Y-axis is set in the downward direction using the upper left corner of the portrait oriented display screen  401  as an origin point. The landscape standard position is data that is used to identify the display position of the icon in the display screen  401  when it is assumed that the display screen  401  is landscape oriented, and the mobile terminal device  101  is held by the dominant hand. In the example, the landscape standard position indicates coordinates of the upper left corner of the icon when the X-axis is set in the right direction, and the Y-axis is set in the downward direction using the upper left corner of the landscape oriented display screen  401  as an origin point. The program name is a name of a program that is stared up by selection of the icon. 
         [0073]    The first record of the example indicates that an icon that is identified by an icon ID “IC-A” is displayed so that the upper left corner of the icon is matched with coordinates (X a1 ,Y a1 ) when the display screen  401  is portrait oriented. In addition, the first record indicates that the icon is displayed so that the upper left corner of the icon is matched with coordinates (X a2 ,Y a2 ) when the display screen  401  is landscape oriented. In addition, the first record indicates that the program “AAA” is started up when the icon is selected. 
         [0074]    The second record of the example indicates that an icon that is identified by an icon ID “IC-B” is displayed so that the upper left corner of the icon is matched with coordinates (X b1 ,Y b1 ) when the display screen  401  is portrait oriented. In addition, the second record indicates that the icon is displayed so that the upper left corner of the icon is matched with coordinates (X b2 ,Y b2 ) when the display screen  401  is landscape oriented. In addition, the second record indicates that the program “BBB” is started when the icon is selected. 
         [0075]    The third record of the example indicates that an icon that is identified by an icon ID “IC-C” is displayed so that the upper left corner of the icon is matched with coordinates (X c1 ,Y c1 ) when the display screen  401  is portrait oriented. In addition, the third record indicates that the icon is displayed so that the upper left corner of the icon is matched with coordinates (X c2 ,Y c2 ) when the display screen  401  is landscape oriented. In addition, the third record indicates that the program “CCC” is started when the icon is selected. 
         [0076]    The fourth record of the example indicates that an icon that is identified by an icon ID “IC-D” is displayed so that the upper left corner of the icon is matched with coordinates (X d1 ,Y d1 ) when the display screen  401  is portrait oriented. In addition, the fourth record that indicates that the icon is displayed so that the upper left corner of the icon is matched with coordinates (X d2 ,Y d2 ) when the display screen  401  is landscape oriented. In addition, the fourth record indicates that the program “DDD” is started up when the icon is selected. 
         [0077]    Returning to the description of  FIG. 9 , the display processing unit  907  displays a display object (in the example, an icon), based on the determination result of the hand that holds the mobile device. The detection unit  909  detects selection of the display object (in the example, the icon). The execution unit  911  executes processing that is related to the selected display object (in the example, the icon). The module configuration of the mobile terminal device  101  is as described above. 
         [0078]    An operation of the mobile terminal device  101  is described below. In a processing flow described below, processing for a display object (in the example, an icon) is described. 
         [0079]      FIG. 11  illustrates a flow of main processing. The determination unit  903  executes determination processing (S 1101 ). 
         [0080]      FIG. 12  illustrates a flow of the determination processing. In the determination processing, whether the hand that holds the mobile device is the left hand or right hand is determined based on the orientation of the display screen  401  when a certain posture of the mobile device is maintained for a certain time period. When the certain posture is not maintained for the certain time period, the posture is not stable, so that the determination processing is continued. 
         [0081]    The determination unit  903  identifies the orientation of the display screen  401  (S 1201 ). The determination unit  903  obtains information that is used to identify the orientation of the display screen  401 , for example, from the display processing unit  907 . Alternatively, the orientation of the display screen  401  may be identified based on the posture angle. 
         [0082]    The determination unit  903  measures the posture angle (S 1203 ). The determination unit  903  measures the roll angle β when the display screen  401  is portrait oriented. The determination unit  903  measures the pitch angle α when the display screen  401  is landscape oriented. For example, the determination unit  903  measures the roll angle β or the pitch angle α using the geomagnetic sensor  833  or the gyro sensor  835 . 
         [0083]    The determination unit  903  determines whether or not the posture angle is a certain angle (for example, 5 degrees) or more in the clockwise direction (S 1205 ). In the case in which the display screen  401  is portrait oriented, when the roll angle β is the certain angle or more in the clockwise direction, the state corresponds to the state in which the mobile device is held by the left hand as illustrated in  FIG. 2 . The determination unit  903  may set an upper limit (for example, 15 degrees) for the posture angle. 
         [0084]    In addition, even when the display screen  401  is landscape oriented, the display screen  401  is generally tilted inward. Thus, also in the case in which the display screen  401  is landscape oriented, when the pitch angle α is the certain angle or more in the clockwise direction, the state corresponds to the state in which the mobile device is held by the left hand. 
         [0085]    That is, regardless of the orientation of the display screen  401 , it is assumed that the mobile device is held by the left hand when the measured posture angle is the certain angle or more in the clockwise direction. 
         [0086]    When the determination unit  903  determines that the posture angle is the certain angle or more in the clockwise direction, the determination unit  903  measures the posture angle similar to the processing of S 1203  (S 1207 ). In addition, the determination unit  903  determines whether or not the posture angle is the certain angle or more in the clockwise direction similar to the processing of S 1205  (S 1209 ). 
         [0087]    When the determination unit  903  determines that the posture angle is less than the certain angle in the clockwise direction, the flow returns to the processing of S 1203 . When the determination unit  903  determines that the posture angle is the certain angle or more in the clockwise direction, the determination unit  903  determines whether or not the certain time period has elapsed in the loop of S 1207  to S 1211  (S 1211 ). 
         [0088]    When the determination unit  903  determines that the above-described certain time period does not elapse, the flow returns to the processing of S 1207 , and the determination unit  903  repeats the above-described pieces of processing. 
         [0089]    When the determination unit  903  determines that the above-described certain time period has elapsed, the determination unit  903  determines that the hand that holds the mobile device is the left hand (S 1213 ), and the determination processing ends. 
         [0090]    On the other hand, when the determination unit  903  determines that the posture angle is less than the certain angle in the clockwise direction in S 1205 , the determination unit  903  determines whether or not the posture angle is a certain angle (for example, 5 degrees) or more in the counterclockwise direction (S 1215 ). In the case in which the display screen  401  is portrait oriented, when the roll angle β is the certain angle or more in the counterclockwise direction, the state corresponds to the state in which the mobile device is held by the right hand as illustrated in  FIG. 1 . 
         [0091]    In addition, even when the display screen  401  is landscape oriented, the display screen  401  is generally tilted inward. Thus, even in the case in which the display screen  401  is landscape oriented, when the pitch angle α is the certain angle or more in the counterclockwise direction, the state corresponds to the state in which the mobile device is held by the right hand. 
         [0092]    That is, regardless of the orientation of the display screen  401 , it is assumed that the mobile device is held by the right hand when the measured posture angle is the certain angle or more in the counterclockwise direction. The determination unit  903  may set an upper limit (for example, 15 degrees) for the posture angle. 
         [0093]    When the determination unit  903  determines that the posture angle is less the certain angle in the counterclockwise direction, the flow returns to the processing of S 1203 . 
         [0094]    On the other hand, when the determination unit  903  determines that posture angle is the certain angle or more in the counterclockwise direction, the determination unit  903  measures the posture angle similar to the processing of S 1203  (S 1217 ). After that, the determination unit  903  determines whether or not the posture angle is the certain angle or more in the counterclockwise direction similar to the processing of S 1215  (S 1219 ). 
         [0095]    When the determination unit  903  determines that the posture angle is less the certain angle in the counterclockwise direction, the flow returns to the processing of S 1203 . 
         [0096]    When the determination unit  903  determines that the posture angle is the certain angle or more in the clockwise direction, the determination unit  903  determines whether or not a certain time period has elapsed in the loop of S 1217  to S 1221  (S 1221 ). 
         [0097]    When the determination unit  903  determines that the above-described certain time period does not elapse, the flow returns to the processing of S 1217 , and the determination unit  903  repeats the above-described pieces of processing. 
         [0098]    When the determination unit  903  determines that the above-described certain time period has elapsed, the determination unit  903  determines that the hand that holds the mobile device is the right hand (S 1223 ), and the determination processing ends. When the determination processing ends, the flow proceeds to the processing of S 1103  illustrated in  FIG. 11 . 
         [0099]    In the above-described example, whether the hand that holds the mobile terminal device  101  is the right hand or left hand is determined based on the posture angle of the mobile terminal device  101 , but the hand that holds the mobile device may be determined by a further method. 
         [0100]    For example, the hand that holds the mobile device may be determined by acceleration that has been measured using the acceleration sensor  837 . In the state illustrated in  FIG. 1 , acceleration in the minus direction of the Y-axis ( FIG. 3 ) is generated under the influence of gravity. On the other hand, in the state illustrated in  FIG. 2 , acceleration in the plus direction of the Y-axis ( FIG. 3 ) is generated under the influence of gravity. Thus, instead of the roll angle β, based on acceleration that is related to the Y-axis ( FIG. 3 ), the state of the mobile terminal device  101  may be determined. 
         [0101]    In addition, when the display screen  401  is landscape oriented, and the mobile terminal device  101  is held by the right hand, acceleration in the plus direction of the X-axis ( FIG. 3 ) is generated under the influence of gravity. Similarly, when the display screen  401  is landscape oriented, and the mobile terminal device  101  is held by the left hand, acceleration in the minus direction of the X-axis ( FIG. 3 ) is generated under the influence of gravity. Thus, instead of the pitch angle α, based on acceleration that is related to the X-axis ( FIG. 3 ), the state of the mobile terminal device  101  may be determined. 
         [0102]    In addition, the hand that holds the mobile device may be determined by a user operation. For example, it may be determined that the mobile device is held by the right hand when the user touches anywhere on the right side of the display screen  401 , and it may be determined that the mobile device is held by the left hand when the user touches anywhere on the left side of the display screen  401 . 
         [0103]    Returning to the description of  FIG. 11 , the display processing unit  907  determines whether or not the hand that is determined to hold the mobile terminal device  101  is the dominant hand (S 1103 ). At that time, the display processing unit  907  identifies the dominant hand in accordance with data that is stored in the dominant hand storage unit  901 . 
         [0104]    When the display processing unit  907  determines that the hand that is determined to hold the mobile terminal device  101  is the dominant hand, the display processing unit  907  executes first display processing (S 1105 ). 
         [0105]      FIG. 13  illustrates a flow of the first display processing. The display processing unit  907  identifies one non-processed display object that is not a display target from among non-processed display objects (in the example, icons) that are set to data that is stored in the display object data storage unit  905  (S 1301 ). For example, the display processing unit  907  sequentially identifies one record that is included in the icon table. 
         [0106]    The display processing unit  907  identifies the orientation of the display screen  401  (S 1303 ), and identifies the standard position of the display object (in the example, the icon) in accordance with the identified orientation of the display screen  401  (S 1305 ). For example, when the display screen  401  is portrait oriented, the display processing unit  907  identifies coordinates that are stored in a field of the portrait standard position that is included in the record of the icon table. When the display screen  401  is landscape oriented, the display processing unit  907  identifies coordinates that are stored in a field of the landscape standard position that is included in the record of the icon table. 
         [0107]    The display processing unit  907  displays the display object (in the example, the icon) in the standard position in accordance with the orientation of the display screen  401  (S 1307 ). For example, the display processing unit  907  displays the icon so that the upper left corner of the icon is matched with the standard position. 
         [0108]    The display processing unit  907  determines whether or not there is a non-processed display object (in the example, the icon) (S 1309 ). For example, the display processing unit  907  determines that there is no non-processed icon when even the final record that is included in the icon table is processed. 
         [0109]    When the display processing unit  907  determines that there is a non-processed display object (in the example, an icon), the flow returns to the processing of S 1301 , and the display processing unit  907  repeats the above-described pieces of processing. 
         [0110]    When the display processing unit  907  determines that there is no non-processed display object (in the example, the icon), in the display processing unit  907 , the first display processing ends. When the first display processing ends, the flow proceeds to the processing of S 1107  illustrated in  FIG. 11 . 
         [0111]    Returning to the description of  FIG. 11 , the detection unit  909  executes first detection processing (S 1107 ). 
         [0112]      FIG. 14  illustrates a flow of the first detection processing. The detection unit  909  determines whether or not a touch event occurs (S 1401 ). When the detection unit  909  determines that a touch event does not occur, the detection unit  909  determines that a display object (in the example, an icon) is not selected (S 1415 ). 
         [0113]    On the other hand, when the detection unit  909  determines that a touch event occurs, the detection unit  909  identifies one non-processed display object (in the example, an icon) that is not a determination target (S 1403 ). For example, the detection unit  909  sequentially identifies a record that is included in the icon table. 
         [0114]    The detection unit  909  identifies the orientation of the display screen  401  (S 1405 ), and identifies the lower right position of a standard range based on the size of the icon (S 1407 ). At that time, the detection unit  909  may obtain data that indicates the orientation of the display screen  401 , for example, from the display processing unit  907 . The standard range corresponds to an area to detect a touch operation, which is used to select a display object (in the example, an icon) in the case in which the mobile device is held by the dominant hand. 
         [0115]      FIG. 15  illustrates the size of an icon. In  FIG. 15 , the width of the icon is represented as “W”, and the height of the icon is represented as “H”. In the example, the standard range corresponds to the boundary of the icon. The boundary of the icon is a rectangle shape, so that the standard range is identified by two points of the upper left corner and the lower right corner of the icon. The upper left corner is matched with the standard position. The x coordinate of the lower right corner is obtained by adding the width W of the icon to the x coordinate of the upper left corner. The y coordinate of the lower right corner is obtained by adding the height H to the y coordinate of the upper left corner. Thus, when the coordinates of the standard position are represented as (X,Y), the coordinates of the lower right corner are represented by (X+W,Y+H). 
         [0116]    The detection unit  909  determines whether or not the touch position is located in the standard range (S 1409 ). For example, the detection unit  909  determines that the touch position is located in the standard range when the x coordinate of the touch position is “X” or more and “X+W” or less, and the y coordinate of the touch position is “Y” or more and “Y+H” or less. 
         [0117]    When the detection unit  909  determines that the touch position is located in the standard range, the detection unit  909  determines that a display object (in the example, an icon) is selected (S 1411 ). In addition, in the detection unit  909 , the first detection processing ends. 
         [0118]    When the detection unit  909  determines that the touch position is not located in the standard range, the detection unit  909  determines whether or not there is a non-processed display object (in the example, an icon) (S 1413 ). For example, the display processing unit  907  determines that there is no non-processed icon when even the final record that is included in the icon table is processed. 
         [0119]    When the display processing unit  907  determines that there is a non-processed display object (in the example, an icon), the flow returns to the processing of S 1403 , and the detection unit  909  repeats the above-described pieces of processing. 
         [0120]    When the display processing unit  907  that there is no non-processed display object (in the example, an icon), the detection unit  909  determines that a display object (in the example, an icon) is not selected (S 1415 ). When the first detection processing ends, the flow proceeds to the processing of S 1109  illustrated in  FIG. 11 . 
         [0121]    Returning to the description of  FIG. 11 , the detection unit  909  determines whether or not a display object (in the example, an icon) is selected by the above-described first detection processing (S 1109 ). When the detection unit  909  determines that a display object (in the example, an icon) is not selected by the above-described first detection processing, the flow returns to the processing of S 1107 , and the detection unit  909  repeats the first detection processing. 
         [0122]    When the detection unit  909  determines that a display object (in the example, an icon) is selected by the above-described first detection processing, the execution unit  911  identifies a program that corresponds to the display object (in the example, the icon) (S 1111 ). In the embodiment, the execution unit  911  identifies a program name that is set to the field of the record of the icon table. The execution unit  911  executes the identified program (S 1113 ). 
         [0123]    On the other hand, when the display processing unit  907  determines that the hand that is determined to hold the mobile terminal device  101  in S 1103  is not the dominant hand, the display processing unit  907  executes second display processing (S 1115 ). 
         [0124]    In the second display processing, using the center axis as a symmetry axis, the display object (in the example, the icon) is displayed at the symmetrical position for the standard position (hereinafter referred to as symmetrical position). Before the second display processing is described, the symmetrical position is described below. In addition, using the center line  403  as a symmetry axis, a range that is symmetrical for the standard range is referred to as a symmetrical range. 
         [0125]      FIG. 17  illustrates an example of the symmetrical position for an icon in the portrait oriented screen. The width of the portrait oriented screen is the length S of the short side, and the height of the portrait oriented screen is the length T of the long side. 
         [0126]    The icon  405   a  on the right side is arranged using the standard position as a reference. When the coordinates of the upper left corner of the standard range are represented as (X,Y), the coordinates of the lower right corner of the standard range are represented by (X+W,Y+H) as described above. The upper left corner of the standard range is the standard position. 
         [0127]    The icon  405   a  on the left side is arranged using the symmetrical position as a reference. The coordinates of the upper left corner of the symmetrical range are represented by (S−X−W,Y), and the coordinates of the lower right corner of the symmetrical range are represented by (S−X,Y+H) as described above. 
         [0128]      FIG. 18  illustrates an example of the symmetrical position for an icon in the landscape oriented screen. The width of the landscape oriented screen is the length T of the long side, and the height of the landscape oriented screen is the length S of the short side. 
         [0129]    The icon  405   a  on the right side is arranged using the standard position as a reference. When the coordinates of the upper left corner of the standard range is represented as (X,Y), the coordinates of the lower right corner of the standard range is represented by (X+W,Y+H) as described above. The upper left corner of the standard range is the standard position. 
         [0130]    The icon  405   a  on the left side is arranged using the symmetrical position as a reference. When the coordinates of the upper left corner of the symmetrical range is represented by (T−X−W,Y), and the coordinates of the lower right corner of the symmetrical range is represented by (T−X,Y+H) as described above. 
         [0131]    As described above, regardless whether the display screen  401  is portrait oriented or landscape oriented, the symmetrical position and the symmetrical range are obtained based on the standard position. 
         [0132]      FIG. 16  illustrates a flow of second display processing. The display processing unit  907  identifies one non-processed display object (in the example, an icon) that is not a display target, similar to the processing of S 1301  (S 1601 ). 
         [0133]    The display processing unit  907  identifies the orientation of the display screen  401 , similar to the processing of S 1303  (S 1603 ), and identifies the standard position of the display object (in the example, the icon), similar to the processing of S 1305  (S 1605 ). In addition, the display processing unit  907  executes symmetrical position calculation processing (S 1607 ). 
         [0134]      FIG. 19  illustrates a flow of the symmetrical position calculation processing. The display processing unit  907  identifies the width L of the screen (S 1901 ). When the display screen  401  is portrait oriented, the length S of the short side is substituted into a parameter of the width L. When the display screen  401  is landscape oriented, the length T of the long side is substituted into the parameter of the width L. 
         [0135]    The display processing unit  907  calculates the x coordinate of the symmetrical position (S 1903 ). The coordinate X of standard position is subtracted from the width L, and the width W of the icon is further subtracted from the width L, so that the x coordinate of the symmetrical position is obtained. 
         [0136]    The display processing unit  907  identifies the y coordinate of the symmetrical position (S 1905 ). The y coordinate of the symmetrical position is equal to the coordinate Y of the standard position. When the symmetrical position calculation processing ends, the flow proceeds to the processing of S 1609  illustrated in  FIG. 16 . 
         [0137]    Returning to the description of  FIG. 16 , the display processing unit  907  displays the display object (in the example, the icon) in the symmetrical position in accordance with the orientation of the display screen  401  (S 1609 ). For example, the display processing unit  907  displays the icon so that the upper left corner of the icon is matched with the symmetrical position. 
         [0138]    The display processing unit  907  determines whether or not there is a non-processed display object (in the example, an icon), similar to the processing of S 1309  (S 1611 ). 
         [0139]    When the display processing unit  907  determines that there is a non-processed display object (in the example, an icon), the flow returns to the processing of S 1601 , and the display processing unit  907  repeats the above-described pieces of processing. 
         [0140]    When the display processing unit  907  determines that there is no non-processed display object (in the example, an icon), in the display processing unit  907 , the second display processing ends. When the second display processing ends, the flow proceeds to the processing of S 1117  illustrated in  FIG. 11 . 
         [0141]    Returning to the description of  FIG. 11 , the detection unit  909  executes second detection processing (S 1117 ). 
         [0142]      FIG. 20  illustrates a flow of the second detection processing. The detection unit  909  determines whether or not a touch event occurs, similar to the processing of S 1401  (S 2001 ). When the detection unit  909  determines that a touch event does not occur, the detection unit  909  determines that a display object (in the example, an icon) is not selected (S 2017 ). 
         [0143]    On the other hand, the detection unit  909  determines that a touch event occurs, the detection unit  909  identifies one non-processed display object (in the example, an icon) that is not a determination target, similar to the processing of S 1403  (S 2003 ). 
         [0144]    The detection unit  909  identifies the orientation of the display screen  401 , similar to the processing of S 1405  (S 2005 ), and identifies the lower right position of the target range based on the size of the icon, similar to the processing of S 1407  (S 2007 ). In addition, the detection unit  909  executes symmetrical range calculation processing (S 2009 ). 
         [0145]      FIG. 21  illustrates a flow of the symmetrical range calculation processing. The detection unit  909  identifies the width L, similar to the processing of S 1901  (S 2101 ). 
         [0146]    The detection unit  909  calculates the x coordinate of the lower right position of the symmetrical range (S 2103 ). The x coordinate of the symmetrical position is obtained by subtracting the coordinate X of the standard position from the width L. 
         [0147]    The detection unit  909  calculates the y coordinate of the lower right position of the symmetrical range (S 2105 ). The y coordinate of the symmetrical position is obtained by adding the height H to the coordinate Y of the standard position. When the symmetrical range calculation processing ends, the flow proceeds to the processing of S 2011  illustrated in  FIG. 20 . 
         [0148]    Returning to the description of  FIG. 20 , the detection unit  909  determines whether or not the touch position is located in the symmetrical range (S 2011 ). For example, the detection unit  909  determines that the touch position is located in the target range when the x coordinate of the touch position is “L−X−W”or more and “L−X” or less, and the y coordinate of the touch position is “Y” or more and “Y+H” or less. 
         [0149]    When the detection unit  909  determines that the touch position is located in the target range, the detection unit  909  determines that a display object (in the example, an icon) is selected, similar to the processing of S 1411  (S 2013 ). In addition, in the detection unit  909 , the second detection processing ends. 
         [0150]    When the detection unit  909  determines that the touch position is not located in the target range, the detection unit  909  determines whether or not there is a non-processed display object (in the example, an icon), similar to the processing of S 1413  (S 2015 ). When the detection unit  909  determines that there is a non-processed display object (in the example, an icon), the flow returns to the processing of S 2003 , and the detection unit  909  repeats the above-described pieces of processing. 
         [0151]    When the detection unit  909  determines that there is no non-processed display object (in the example, an icon), the detection unit  909  determines that a display object (in the example, an icon) is not selected, similar to the processing of S 1415  (S 2017 ). When the second detection processing ends, the flow proceeds to the processing of S 1119  illustrated in  FIG. 11 . 
         [0152]    Returning to the description of  FIG. 11 , the detection unit  909  determines whether or not a display object (in the example, an icon) is selected by the above-described second detection processing (S 1119 ). When the detection unit  909  determines that a display object (in the example, an icon) is not selected by the above-described second detection processing, the flow returns to the processing of S 1117 , and the detection unit  909  repeats the second detection processing. 
         [0153]    When the detection unit  909  determines that a display object (in the example, an icon) is selected by the above-described second detection processing, the execution unit  911  identifies a program that corresponds to the display object (in the example, the icon) as described above (S 1111 ). The execution unit  911  executes the identified program (S 1113 ). The operation of the mobile terminal device  101  is as described above. 
         [0154]    The above-described icon is an example of a display object. The display object may be a further interface component. For example, the display object may be a widget such as a button, a list, a menu, a bar, a tab, a label, a box, or a window. 
         [0155]    In the embodiment, regardless whether the user holds the mobile device with the left hand or right hand, a positional relationship between a display object (for example, an icon) and the hand becomes same. Thus, the usability is caused to become similar between the case in which the mobile device is held by the right hand and the case in which the mobile device is held by the left hand. For example, a display object at a position that is seldom covered by the thumb of the right hand when the user holds the mobile device with the right hand is displayed at a position that is seldom covered by the thumb of the left hand when the user holds the mobile device with the left hand. 
         [0156]    In addition, regardless whether the user holds the mobile device with the left hand or right hand, an operation by a similar finger movement may be performed for the same display object (for example, an icon). For example, a display object that is located at a position that is easily touched by the thumb of the right hand when the user holds the mobile device using a touch panel with the right hand is easily touched by the thumb of the left hand even when the user holds the mobile device with the left hand. 
         [0157]    In addition, the user may perform an operation that causes the same program to be started up with a similar finger movement using either hand. 
         [0158]    In addition, the center line is used as a symmetry axis, so that the symmetrical position and the symmetrical range for a display object may be included within the display screen. 
       Second Embodiment 
       [0159]    In the embodiment, an example is described in which arrangement of a numeric keypad is changed depending whether the hand that holds the mobile terminal device  101  is the left hand or right hand. 
         [0160]    The numeric keypad is an example of a display object. The display object according to the embodiment includes a plurality of interface components that is in accordance with certain arrangement. For example, the numeric keypad includes a plurality of numeric key buttons that are in accordance with certain arrangement. 
         [0161]    In the embodiment, it is assumed that a plurality of interface components (in the example, numeric key buttons) is displayed in accordance with certain arrangement when a display object (in the example, a numeric keypad) is displayed. 
         [0162]      FIG. 22  illustrates an example of a numeric keypad. The numeric keypad includes 12 numeric key buttons that are arranged in four rows and three columns. In the first row, a numeric key button “1”, a numeric key button “2”, and a numeric key button “3” are arranged from left to right. In the second row, a numeric key button “4”, a numeric key button “5”, and a numeric key button “6” are arranged from left to right. In the third row, a numeric key button “7”, a numeric key button “8”, and a numeric key button “9” are arranged from left to right. In the fourth row, a numeric key button “*”, a numeric key button “0”, and a numeric key button “#” are arranged from left to right. 
         [0163]    In the embodiment, as illustrated in  FIG. 22 , the width of a numeric keypad  2201  is represented by “W”, and the height of the numeric keypad  2201  is represented by “H”. 
         [0164]      FIG. 23  illustrates an arrangement example of the numeric keypad, which is suitable when the right-handed user uses the numeric keypad with the right hand. In the example, the numeric keypad  2201  is arranged on the right side of the display screen  401 . Therefore, numeric key buttons are easily touched by the thumb of the right hand that is the dominant hand. However, when the mobile device is held by the left hand that is opposite to the dominant hand, any numeric key button is seldom touched by the thumb of the left hand. 
         [0165]    Also in the second embodiment, similar to the first embodiment, when the mobile terminal device  101  is held by the hand that is opposite to the dominant hand, the position at which the numeric keypad is arranged is changed. 
         [0166]      FIG. 24  illustrates an arrangement example of the numeric keypad, which is suitable when the right-handed user uses the numeric keypad with the left hand. As illustrated in  FIG. 24 , the position of the numeric keypad  2201  is changed to the symmetrical position using the center line  403  as a symmetry axis. When the position of the numeric keypad is changed as described above, the numeric key buttons are easily touched by the thumb of the left hand. 
         [0167]    As illustrated in  FIG. 23 , when the standard position of the numeric keypad  2201 , that is, the coordinates of the upper left corner are represented as (X,Y), the coordinates of the lower right corner are represented by (X+W,Y+H). 
         [0168]    In addition, as illustrated in  FIG. 24 , the symmetrical position of the numeric keypad  2201 , that is, the coordinates of the upper left corner are represented by (S−X−W,Y), and the coordinates of the lower right corner are represented by (S−X,Y+H). 
         [0169]    In the above-described examples, the case is described in which the display screen  401  is portrait oriented, but such examples are also applied to the case in which the display screen  401  is landscape oriented. The case in which the display screen  401  is landscape oriented is described using  FIGS. 25 and 26 . 
         [0170]      FIG. 25  illustrates an arrangement example of the numeric keypad, which is suitable when the right-handed user uses the numeric keypad with the right hand. In the example, the numeric keypad  2201  is arranged on the right side of the display screen  401 . Therefore, the numeric key buttons are easily touched with the thumb of the right hand that is the dominant hand. However, when the mobile device is held by the left hand that is opposite to the dominant hand, any numeric key button is seldom touched by the thumb of the left hand. 
         [0171]    Also in the second embodiment, similar to the first embodiment, when the mobile terminal device  101  is held by the hand that is opposite to the dominant hand, the position at which the numeric keypad is arranged is changed. 
         [0172]      FIG. 26  illustrates an arrangement example of the numeric keypad, which is suitable when the right-handed user uses the numeric keypad with the left hand. As illustrated in  FIG. 26 , the position of the numeric keypad  2201  is changed to the symmetrical position using the center line  601  as a symmetry axis. When the position of the numeric keypad is changed as described above, the numeric key buttons are easily touched by the thumb of the left hand. 
         [0173]    As illustrated in  FIG. 25 , when the standard position of the numeric keypad  2201 , that is, the coordinates of the upper left corner are represented as (X,Y), the coordinates of the lower right corner are represented by (X+W,Y+H). 
         [0174]    In addition, as illustrated in  FIG. 26 , the symmetrical position of the numeric keypad  2201 , that is, the coordinates of the upper left corner are represented by (T−X−W,Y), and the coordinates of the lower right corner are represented by (T−X,Y+H). 
         [0175]    In the embodiment, in the display object data storage unit  905 , a display object table that is described below is stored instead of the above-described icon table. 
         [0176]      FIG. 27  illustrates an example of the display object table. A record is included for each display object. The record includes a field that is used to set a display object ID, a field that is used to set a portrait standard position, a field that is used to set a landscape standard position, and a field that is used to set a program name. 
         [0177]    The display object ID is an identifier that is used to identify a display object (in the example, a numeric keypad). The portrait standard position is a data that is used identify the display position of the display object (in the example, the numeric keypad) in the display screen  401  when it is assumed that the display screen  401  is portrait oriented, and the mobile terminal device  101  is held by the dominant hand. In the example, the data indicates the coordinates of the upper left corner of the display object (in the example, the numeric keypad) when the X-axis is provided in the right direction, and the Y-axis is provided in the downward direction by setting the upper left corner of the portrait oriented display screen  401  as an origin point. The landscape standard position is data that is used to identify the display position of the display object (in the example, the numeric keypad) in the display screen  401  when it is assumed that the display screen  401  is landscape oriented, and the mobile terminal device  101  is held by the dominant hand. In the example, the data indicates the coordinates of the upper left corner of the display object (in the example, the numeric keypad) when the X-axis is provided in the right direction, and the Y-axis is provided in the downward direction by setting the upper left corner of the landscape oriented display screen  401  as an origin point. The program name is a name of a program that is a destination to which an even that occurs in the display object (in the example, the numeric keypad) is notified. 
         [0178]    The record of the example indicates that a display object that is identified by a display object ID “OB-T” is displayed so that the upper left corner of the display object is matched with the coordinates (X t1 ,Y t1 ) when the display screen  401  is portrait oriented. In addition, the record indicates that the display object is displayed so that the upper left corner of the display object is matched with the coordinates (X t2 ,Y t2 ) when the display screen  401  is landscape oriented. In addition, the record indicates that an event that occurs in the display object is notified to a program “TTT”. 
         [0179]      FIG. 28  illustrates a flow of main processing in the second embodiment. The processing of S 1101  to S 1111  is similar to that of the first embodiment. However, instead of the processing of identifying the portrait standard position, the landscape standard position, and the program name, based on the icon table illustrated in  FIG. 10  in the first embodiment, in the second embodiment, a portrait standard position, a landscape standard position, and a program name are identified based on the display object table illustrated in  FIG. 27 . 
         [0180]    In addition, in S 1307  of  FIG. 13  and S 1609  of  FIG. 16 , when a display object is displayed, interface components (in the example, numeric key buttons) are displayed in accordance with certain arrangement (for example, the arrangement illustrated in  FIG. 22 ). 
         [0181]    In addition, in S 2801 , the execution unit  911  notifies the program that has been identified in S 1111  of an event that has occurred in the display object (in the example, the numeric keypad). For example, the execution unit  911  may notify the program of an ID of an interface component (in the example, an ID of the numeric key button) that is included in the display object. Alternatively, the execution unit  911  may notify the program of a code (in the example, a numeric code) that corresponds to the ID of the interface component (in the example, the ID of the numeric key button) that is included in the display object. Alternatively, the execution unit  911  may notify the program of a relative touch position in the display object (in the example, the numeric keypad). 
         [0182]    The example of the numeric keypad is as described above, but the display object may be a character key array that includes a plurality of character key buttons. In this case, the character key button is an example of an interface component. In addition, an ID of the character key button corresponds to an ID of the interface component, and the character code corresponds to a code that corresponds to the ID of the interface component. 
         [0183]    In the embodiment, regardless whether the user holds the mobile device with the left hand or right hand, a positional relationship between interface components that are included in the display object may be caused not to be changed. For example, in the case of the display object such as the numeric keypad, confusion of the user may not be caused as long as the numeric key buttons are not replaced with each other. 
         [0184]    The description of the embodiments is made above, but the embodiments are not limited to such a description. For example, the above-described function block configuration may not be matched with an actual program module configuration. 
         [0185]    In addition, the above-described configuration of each of the storage areas is just an example, and the embodiment is not limited to the above-described configuration. In addition, also in the processing flows, the order of the pieces of processing may be changed as long as the processing result is not changed. In addition, the pieces of processing may be executed in parallel. 
         [0186]    The conclusion of the above-described embodiments is as follows. 
         [0187]    A mobile device according to an embodiment includes a determination unit that determines whether or not the mobile device is held by the right hand or the left hand, and a display processing unit that displays a display object in the symmetrical position for a reference position in which the display object is to be displayed, using a vertical axis as a symmetry axis in a display screen when the determination unit determines that the mobile device is held by the opposite hand to a reference hand. 
         [0188]    Therefore, regardless whether the user holds the mobile device with the left hand or the right hand, a positional relationship between the display object and the hand becomes same. Thus, the usability may be caused to become similar between the case in which the mobile device is held by the right hand and the case in which the mobile device is held by the left hand. For example, a display object in a position that is seldom covered by the thumb of the right hand when the user holds the mobile device with the right hand is displayed in a position that is seldom covered by the thumb of the left hand when the user holds the mobile device with the left hand. 
         [0189]    In addition, the above-described mobile device may include a detection unit that detects an event for the display object in a symmetrical range for a reference range in which the event is to be detected in accordance with the above-described symmetry axis when the determination unit determines that the mobile device is held by the opposite hand to the reference hand. 
         [0190]    Therefore, regardless whether the user holds the mobile device with the left hand or right hand, an operation by a similar finger movement may be performed on the same display object. For example, a display object at a position that is easily touched by the thumb of the right hand when the user holds the mobile device that includes the touch panel with the right hand is easily touched by the thumb of the left hand even when the user holds the mobile device with the left hand. 
         [0191]    In addition, the above-described mobile device includes an execution unit that executes a program that is related to the display object when the above-described mobile device detects the above-described event. 
         [0192]    Therefore, the user may perform an operation that causes the same program to be started up by a similar finger movement using either hand. 
         [0193]    In addition, the display object may include a plurality of interface components that is in accordance with certain arrangement. In addition, when the display object is displayed, the above-described display processing unit may display the plurality of interface components in accordance with the above-described certain arrangement. 
         [0194]    Therefore, regardless whether the user holds the mobile device with the left hand or right hand, a positional relationship between the interface components that are included in the display object may be caused not to be changed. For example, in the case of the display object such as the numeric keypad, confusion of the user may not be caused as long as the numeric key buttons are not replaced with each other. 
         [0195]    In addition, when the display screen is portrait oriented, the above-described vertical axis may be in parallel with the long side of the display screen, and may be an axis that has the same distance from the left end and the right end of the portrait oriented display screen. In addition, when the display screen is landscape oriented, the above-described vertical axis may be in parallel with the short side of the display screen, and may be an axis that has the same distance from the left end and the right end of the landscape oriented display screen. 
         [0196]    Therefore, both of the symmetrical position and the symmetrical range of the display object may be included within the display screen. 
         [0197]    A program that is used to cause a processor to execute processing in the above-described mobile device may be created, and the program may be stored, for example, in a computer-readable storage medium such as a flexible disk, a CD-ROM, a magneto optical disk, a semiconductor memory, or a hard disk, or a storage device. The intermediate processing result is generally stored in the storage device such as a main memory temporarily. 
         [0198]    All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.