A mobile phone handset includes a mode switching unit and a configuration detection sensor, so that the operating mode of the mobile phone handset can be switched. The mode switching unit has a switching program installed, and is a computer for executing a prescribed process in accordance with the switching program when a signal is input from the configuration detection sensor. The configuration detection sensor is a sensor for detecting the configuration of the mobile phone handset, and for example may use an angular sensor for detecting the relative angle about a rotation axis between a first casing and a second casing.