A system of transmitting content, such as text messaging content, among a plurality of mobile communication devices. The system comprises a plurality of transmission management modules installed in a plurality of mobile communication devices, each being adapted to transmit messaging content and a target telephone number via a packet-oriented communication link and a messaging router which receives the content and the target telephone number via the packet-oriented communication link from one of the plurality of mobile communication devices, identifies a target packet-oriented communication address according to the target telephone number and routes the content to another of the plurality of mobile communication devices according to the target packet-oriented communication address.