wow this is pretty darn good. I have been searching quite hard for video players that will let you switch audio/subtitle tracks. I have tried AV player, rushplayer, azul media player and they fail at it. Ace Player has this function though!
However, video playback is a bit choppy for 720p mkv files( is it not making use of ipad 2's 2 cores and hardware acceleration?). Well you can achieve relatively smooth playback if you enable frame skipping, but there really shouldn't be a need to compromise on the quality of the videos! There are times where the audio and the subtitles seem to be out of sync. If only I could merge the super smooth video playback of rush player with the functionality of Ace Player =/
Well, it is a promising video/movie player and its free.