Playing video on ones cell or iPod requires that the files be in a 3GP format, MediaCell Video Converter is the best software for MP4/3GP file conversion for such Devices. MediaCell Converter introduces unmatchable video compression ratio and conversion speed (7 times of the playback). Download link is at the end of this post.
The technology that lies behind MediaCell allows us to re-compress video files without causing any addition loss in video quality. Give it a try the software comes with a Free 14 day trial version. You can download it from [HERE!]