User terminal and method of displaying lock screen thereof

A user terminal device comprising:

• a display unit, comprising a display, configured to display a lock screen, wherein the lock screen comprises content representative information representing content included in a message that is provided by an acquaintance of a user of the user terminal device, and a first user interface element;
• and
• a control unit, comprising a processor, configured to, when a user input signal is received via the first user interface element, execute an application capable of reproducing the content and to reproduce the content.

A server that provides content to be displayed on a lock screen of a user terminal device, the server comprising:

• a control unit, comprising a processor, configured to determine at least one acquaintance to be provided with content recommended by a user of a first user terminal device, wherein the at least one acquaintance is an acquaintance of the user;
• and
• a communication unit, comprising a transmitter, configured to transmit, to a second user terminal device of the at least one acquaintance, (i) at least one of representative information of the content, a portion of the content, and information about a location where the content is stored, and (ii) content display screen information indicating that the content is displayed on a lock screen of the second user terminal device.

A non-transitory computer readable recording medium on which a program for implementing a method of displaying a lock screen on a user terminal device is recorded, the method comprising:

• displaying a lock screen on a display unit, wherein the lock screen comprises content representative information representing content included in a message provided by an acquaintance of a user of the user terminal device, and a first user interface element;
• and
• when a user input signal is received via the first user interface element, executing an application capable of reproducing the content, and reproducing the content using the application.