“entropic” from HandBrake forum wrote a little tool called “Muxo” to add subtitles to mp4, so your iPhone can play with soft subtitle. Muxo is a small Mac OS X cli-tool that adds subtitle tracks to existing mp4 files. Now, it’s in a really early stage, and the tool only reads srt files. You can direct download the tool: Muxo 0.3.3 from here or from my mirror.
screenshot:
Play with iPhone:



















This seems great but… Do you know if it works on iPods?
It works on iPod Touch, I think it also works on new ipod nano
I want to instal muxo on Windows Vista. I can’t. Please help. Thank you.