I have got FFmpeg compiled (libffmpeg.so) on Android. Now I have to build either an application like RockPlayer or use existing Android multimedia framework to invoke FFmpeg
To make my FFMPEG application I used this project (https://github.com/hiteshsondhi88/ffmpeg-android-java) so, I don't have to compile anything. I think it's the easy way to use FFMPEG in our Android applications.
More info on http://hiteshsondhi88.github.io/ffmpeg-android-java/