Where do I find anime in 720p.

But get this... the file format is mp4...

AND THEN it has to be L3.1 or below, for my Vita

Woah Woah Woah Slow down sir

You wait until someone cracks the vita and adds proper media capabilities to it.

(or use a converter for mkv to mp4, but you will lose quality)

oh yeah
forgot how crappy handheld consoles were

I watch a good 70% of my anime on my (android) phone.
The looking for "MX Player" on the android market, it's played every file type I've asked it to so far.

Damn i have a Whole Memory card for my Vita filled with Anime and it plays it without problem and comes out looking great.
and the screens big enough for the subtitles not to be to small so its pretty awesome, probably my favorite way to take Anime around with me so far.

Oh I'm sure. Are you converting it yourself, or do you have a source.