If you need both at the same time, only exPlayer HD (by Zhigang Chen http://itunes.apple.com/app/explayer-hd/id418100406?mt=8 ). XBMC also supports both simultaneously BUT it doesn't support iPad 3 Retina and requires jailbreaking.
If pre-downloading (vs. streaming) is OK (pre-downloaded files are easy to play back in HW), a lot more players are available. Let me know if you need more info on the latter players.