USER TERMINAL APPARATUS, COMMUNICATION SYSTEM AND CONTROL METHOD THEREOF

摘要

Disclosed is a user terminal device which supports an instant messenger service. The user terminal device includes: a display unit which provides an instant messenger service screen including an output message; and a control unit that decrypts an encrypted message according to a predetermined event, if the output message is the encrypted message, and provides the decrypted message to the screen or another screen, different from the screen.