1. A mobile device comprising: a touch screen for displaying a screen and for detecting a touch input; a sensing module for detecting a proximity input; a storage unit configured to store one or more programs used to operate the mobile device and to store data generated when the one or more programs are executed; and one or more processors configured to: control the touch screen to display a Graphical User Interface (GUI); determine whether the proximity input is detected by the sensing module when the touch input is detected; perform a first function according to the touch input corresponding to the GUI if the proximity input is not detected; and perform a second function according to the touch input corresponding to the GUI while the proximity input is detected.