The idea has come up here several times to release audio projects as apps for use on iPhone / iPad / etc. Not because that format has any technical advantage over standard mp3 files, but because there is a huge pool of device owners looking for content - especially *free* content.
If you are interested in seeing how one company has tried this, check out this free download of Tolkien's The Hobbit
audiobook. It is a free downloadable app today, but is pretty cheap anyway if you miss the deadline for the freebie. Reviewers comments on the iTunes store are very positive for this item - maybe just 'cuz its free, or maybe because they really like the format and would welcome more releases like it.
Download site: http://itunes.apple.com/us/app/j.tol...452281804?mt=8
Anyone else tried this methodology for distribution of Audio Theatre?
(Standard disclaimer - I'm not connected to the company; just pointing out an interesting offer.)