A flexible LCD (2) is a flexible display. The flexible LCD (2) is pulled out from an upper cabinet to change a display area of the flexible LCD (2). An amount-of-sliding detecting section (4) measures the pullout amount (amount of sliding) of the flexible LCD (2) when the flexible LCD (2) is pulled out from a mobile terminal unit (1) or is retracted into the mobile terminal unit (1). A display controller (3) causes the flexible LCD (2) to display in a manner responsive to the amount of sliding that is measured by the amount-of-sliding detecting section (4). The foregoing makes it possible to utilize effectively the display having a display area that is revealed when the display is pulled out.