1. A method for setting a relationship between users of a plurality of mobile terminals, the method comprising: receiving, from the plurality of mobile terminals, information on gestures made on, and recognized at, the plurality of mobile terminals, respectively, with respect to a single user gesture; determining a gesture correlation between the recognized gestures and the single user gesture based on the information on the recognized gestures; and setting a relationship between users of the plurality of mobile terminals based on the gesture correlation.