An expanded function supporting method and a mobile device adapted thereto are provided. The method includes receiving input signals for activating a user function related to a system installed to a mobile device, establishing a basic function supporting path used to operate the system when the user function is activated, and an expanded function supporting path to operate an expanded function of the system when an input signal for operating the expanded function is received, and transferring, when receiving an input signal for operating the expanded function, a command for operating the expanded function via the expanded function supporting path.