A mobile phone apparatus is provided with an accelerometer for detecting an attitude and a display for displaying a moving object. Furthermore, a key locked state is set to the mobile phone apparatus for the purpose of preventing an operating error in the key. When an arbitrary key is operated in the key locked state, the moving object and a pocket object representing a predetermined area, etc. are displayed on the display. Then, when the moving object changes in position in correspondence with the change of the attitude of the mobile phone apparatus and is put into the pocket object, the key locked state is cancelled.