along with an input applied thereto more specifically a fingerprint recognition sensor e g fingerprint scanner module may be mounted on one surface central button of the button or a front surface thereof to recognize a finger 39 s fingerprint and contact direction brought into contact with the button therethrough the button is slidably formed by the push thereby pressurizing a switch when the switch is pressurized the controller senses a push input to process control command corresponding to the relevant push input however the present disclosure may not be necessarily limited to this the foregoing structure for example the push button may be replaced by touch button more specifically a fingerprint recognition sensor may be disposed on one surface central button of the touch button accordingly according to an example which will be described below an input through the button may be replaced by a touch input through a touch button from the foregoing configuration of the rear input unit the present disclosure may provide a scheme of allocating at least one or more functions executable on each module to guide them to the front display unit when a user 39 s first input to the rear input unit is sensed and recognizing the direction of the relevant input through the fingerprint recognition sensor to execute a function allocated to the relevant direction when a second input is sensed the first input may be an input to a specific button for example an input to a central button and the second input may include an input to all buttons constituting.