Completed Android to Node.js+Socket.io WebSocket chat system.
Multiple Android client can connect to http://49.128.39.190:8887 and chat to each other, provided the server is up and running.
Each client emits a "chat" event to the server, which emits a "chat" event to all clients.
Each client that receives a "chat" event display the .username and .message contents.
Possible to expand the implementation to include "mid" and "target" keys in the event data to client specific display, like in webrtc-enterprise.
Even stronger level of recipient specification can be acheived at the server by emitting only to specific client.
io.sockets.socket(socketid).emit('message', 'for your eyes only');
Reference:
https://github.com/LearnBoost/socket.io/wiki/How-do-I-send-a-response-to-all-clients-except-sender%3F