An information processing device comprising: a chassis with a front surface and a back surface, wherein the chassis extends in a width direction (X), a height direction (Y) and a depth direction (Z); a display section on the front surface of the chassis ; a front touch sensor that overlaps the display section and is adapted to detect a position of an object on a front detection surface of the front touch sensor ; a back touch sensor on the back surface of the chassis that is disposed opposed to the front touch sensor and adapted to detect a position of an object on a back detection surface of the back touch sensor ; and a control section being connected to the front touch sensor and the back touch sensor via an input interface , characterized in that the control section is adapted to identify, as a prohibited area , one of two areas that each occupy a part of the display section and are disposed on a lower left or lower right area of the display section based on at least one detected position (S109) by the back touch sensor , said at least one detected position (S109) determines whether the information processing device is grasped by a left or right hand of a user, the prohibited area being set as the area that is hidden by the other operating hand of the user, and the control section is adapted to cause information as a display target to be displayed in one or more priority areas (54-1, 54-2, 54-3) outside the prohibited area in the display section , and wherein a correspondence relationship between the detected position (S109) by the back touch sensor and the prohibited area identified from the two areas is changed depending on a determination by an orientation detector that is adapted to determine whether a user grasps the device laterally along the height direction (Y) being associated to a shorter-side direction of the display section or longitudinally along the width direction (X) being associated to a longer-side direction of the display section . a chassis with a front surface and a back surface, wherein the chassis extends in a width direction (X), a height direction (Y) and a depth direction (Z); a display section on the front surface of the chassis ; a front touch sensor that overlaps the display section and is adapted to detect a position of an object on a front detection surface of the front touch sensor ; a back touch sensor on the back surface of the chassis that is disposed opposed to the front touch sensor and adapted to detect a position of an object on a back detection surface of the back touch sensor ; and a control section being connected to the front touch sensor and the back touch sensor via an input interface , characterized in that the control section is adapted to identify, as a prohibited area , one of two areas that each occupy a part of the display section and are disposed on a lower left or lower right area of the display section based on at least one detected position (S109) by the back touch sensor , said at least one detected position (S109) determines whether the information processing device is grasped by a left or right hand of a user, the prohibited area being set as the area that is hidden by the other operating hand of the user, and the control section is adapted to cause information as a display target to be displayed in one or more priority areas (54-1, 54-2, 54-3) outside the prohibited area in the display section , and wherein a correspondence relationship between the detected position (S109) by the back touch sensor and the prohibited area identified from the two areas is changed depending on a determination by an orientation detector that is adapted to determine whether a user grasps the device laterally along the height direction (Y) being associated to a shorter-side direction of the display section or longitudinally along the width direction (X) being associated to a longer-side direction of the display section . <EOS>