I'd like to add multiplayer to one of my android strategy games.
Are there any free MP frameworks you can recommend? The server can be implemented in any language/environment. But the client needs to be Java, as I'm not using NDK. Since this is all hobby work, it needs to be free (or extremely cheap).
My main requirement is real-time messaging (~ 1-2 second delays). I haven't even decided if I want to support WAN. If you have something which is LAN only (one of the clients is the server), that might be enough.
Is there a staple opensource multi-player engine?
Also, while I was pondering the problem, google released this:
https://developers.google.com/games/services/android/multiplayer
Would you recommend using it?
Do you know what the pricing model is?
Have you used it before?