A mobile terminal includes a position location module, a wireless communication unit, a user input unit, and a controller. The controller is configured to obtain first position information via the position location module in response to a first command received via the user input unit, receive second position information via the wireless communication unit, wherein the second position information relates to a geographical location of the external device, identify a relative distance between the mobile terminal and the external device using the first position information and the second position information, and perform an interlock function at the mobile terminal in response to a second command received via the user input unit if the relative distance between the mobile terminal and the external device is less than a threshold distance, where the interlock function restricts the mobile terminal from performing a function.