Mobile electronic device and recording medium

A computer-readable recording medium having stored therein a key display program for a mobile electronic device that comprises:

• a display that has a touch panel function, and a processor that displays a key on the display, the key display program causing the processor to execute a process comprising:
• when an operation key group having a plurality of keys arranged within a predetermined area is displayed on the display,
• displaying, in a switchable manner, a first arrangement in which each of the keys of the operation key group is arranged within the predetermined area, and a second arrangement in which at least one of the keys of the operation key group is deleted or arranged in a size smaller than a size of a key that is in the first arrangement and that corresponds to the one of the keys and in which a handwriting input area is arranged at a space area that is generated within the predetermined area as the one of the keys is deleted or arranged in a smaller size.