Although the server application is available for Windows only at the time you can easily create your own implementations for your favorite Linux distribution, Arduino or basically anything you can think of without touching the Android application. Messages are exchanged in JSON encoded format through UDP packets. Check out the documentation of used ports and available messages at freemotecontrol.com.
There is still much more to be done. Feedback, feature requests and contributions are more than welcome.
For details, please visit: http://freemotecontrol.com