An application program installed in a user terminal including a user interface unit for displaying a list of music files; a playback unit for playing back a music file selected out of the list; a transfer unit for transferring the selected music file to a certain storage medium; and a control unit for controlling the playback unit to play back the selected music file. The list being controlled at the same time to display an operation menu below music information of the music file being played back, if a playback request signal is input through the user interface unit, and controlling the transfer unit to transfer the selected music file, if a transfer request signal is input.