How to implement a h.264 encoder at mobile platform(android, ios, symbian)

As far as I know, not all the mobile platform(android, ios, symbian) support h.264 encoding. Now I want to implement a h.264 encoder at mobile platform, encoding the videos and transfer them from one mobile phone to another. I found ffmpeg is useful, but I cannot find some useful tutorial. And is there some other efficient methods? Thanks!

update:I have read that manual before and found android 2.1+ does开发者_如何学C not support h.264 encoding. Different means of implementing h.264 video encoding on each OS or a way of doing this in a cross-platform manner are both ok :-)

How about http://developer.android.com/reference/android/media/MediaRecorder.html?

There is also a link to how the AudioRecorder is used. Guess the procedure is the same for video.