Abstract: There is disclosed an application controller for use with a two-way wireless messaging system. The application controller is distributed, at least in part, among a plurality communication units associated with the two-way wireless messaging system. The application controller is capable of controlling cooperative communication among ones of the communication units in accordance with a prescribed application task, and comprises a data repository, first and second communication controllers, and an operations controller. The data repository maintains at least one subscriber profile. The first communication unit controller senses change in a characteristic monitored at a first communication unit, wherein the monitored characteristic is evaluated in accordance with the prescribed application task, and, in response thereto, automatically causes the first communication unit to transmit a first data signal.