An electronic device can operate as an external device of an information processing apparatus. The electronic device includes a connecting unit for connecting to the information processing apparatus, a command processor for processing a command sent from the information processing apparatus through the connecting unit, a rechargeable battery, a charging controller for controlling a charging operation of the rechargeable battery, and an operating mode managing unit which, when the connecting unit is connected to an interface having a power-supply function, selects one of a normal operating mode in which the electronic device operates as the external device of the information processing apparatus, and a charging mode in which the electronic device stops operating as the external device of the information processing apparatus and charges the rechargeable battery. The command processor processes the command in accordance with the selected operating mode.