1. A mobile phone having a non-telephone function, which is a different function from a telephone function, in addition to the telephone function, comprising: a timer operable to count time; a non-telephone function unit operable to execute the non-telephone function, the non-telephone function comprising a function of illuminating a backlight provided to the mobile phone; a non-telephone function stop unit operable to cause the timer to operate during execution of the non-telephone function, and automatically stop the execution of the non-telephone function when the timer indicates an elapse of a predetermined time period; a telephone unit operable to execute the telephone function; and a reset unit operable, if the timer is being operated in response to the execution of the non-telephone function, to reset the timer to an initial state when a certain operation relating to an application is executed, wherein when the timer is reset to the initial state, the timer starts to measure the predetermined time period, and the non-telephone function stop unit stops the execution of the non-telephone function at the elapse of the predetermined time period from when the certain operation relating to an application is executed.