A mobile intercom device is described that is configured to facilitate the assignment and reassignment of functions during use. A plurality of button pairs, each including a talk button and a listen button, and a display screen are provided on the mobile intercom device. An electronic processor of the mobile intercom device is configured to display a list of alphanumeric identifiers on the display screen, each alphanumeric identifier in the list of alphanumeric identifiers corresponding to a different one of a plurality of channels on the intercom system. A selection of a first alphanumeric identifier from the list is received and a channel on the intercom system corresponding to the first alphanumeric identifier is assigned to a first button pair of the plurality of button pairs.