Finally implemented WebSocket client within app
Failed with:
- socket.io (had to revert to version 0.9, which is poorly documented, too much hassle)
- GCM (poor documentation, Python CCS would not even work with Google App Engine..)

Current implementation =
Node.js + WebSocket (npm install ws)
https://github.com/einaros/ws
Android + Java-WebSocket
https://github.com/TooTallNate/Java-WebSocket
Merged commit