Okay, I pretty much felt like one of the students in Charlie Brown's class. You know, where they hear "Wha wha wha."
Very humbing to realize how much out there I don't know/never heard of
However, how about this page?
Pro Music Apps » MIDI
It seems like a pretty cool site for MIDI apps (?). In fact, the whole site is pretty interesting... They may have some articles or whatnot about that dock.
Other than that, I'll let an expert come along to help...
Marilyn
P.S. If it's of any use to you, I've got the Symphonix Evolution Player app and it plays MIDIs quite nicely (for what I need)...