When an off-hook key is pressed in the power-off state, a power control unit applies power to circuits including a radio communication unit. When a camera mode startup power on/off key (manner key in the phone mode) provided on the side of the body is pressed in the power-off state, the power control unit applies power from a power supply to each circuit except the radio communication unit, whereby the signal-off mode is set and an imaging device, DSP and subdisplay unit are activated. After that, when a shutter key (memo key in the phone mode) is pressed, an image at that time is captured and stored into a RAM.