Patent ID: 8750937

Claim:
A mobile terminal device comprising: a plurality of keys, each of which are previously assigned different functions including at least a first function and a second function, the first function corresponding to a key that is depressed after one of the plurality of keys has been touched for equal to or longer than a predetermined judging time, and the second function corresponding to a key that is depressed after one of the plurality of keys has been touched for less than the predetermined judging time; a touch detector configured to detect touching any of the keys by a user; a press detector configured to detect a depression of any of the keys by the user; an output unit configured to simultaneously output explanations on all of the first functions previously assigned to all of the plurality of keys when a touching time period for which the user touches a first key of the plurality of keys is equal to, or longer than, the predetermined judging time; and a function executor configured to execute the first function of a second key when the press detector detects a depression of the second key by the user in a case where the explanations on all of the first functions previously assigned to all of the plurality of keys are being simultaneously output and a touching time period for which the user touches the first key is equal to, or longer than, the predetermined judging time, wherein the output unit simultaneously outputs all of the explanations on the first functions previously assigned to the respective keys on a display when the touching time period for any of the keys is equal to, or longer than, the predetermined judging time; and the display unit displays the explanation on the first function previously assigned to the touched key in a state where the display of the explanation is in a manner which is emphasized or distinguished over the displays of the remaining explanations on the first functions of the remaining keys.