bigfish

bisfish is a crossplattform library that can be used with IPhone, Android and Windows Phone 7 projects. It enables you to easily share data between the three platforms.
You run a server (programmed in java) to that all the clients will connect. The clients can choose a session to join with. A session can be password protected. In a session you can send messages (bytes) to all of the members of a session, to a group of members or to a single member (broadcast, multicast and unicast).