If you’re into adaptive/interactive music, you should definitely check out the Biophilia app by Björk. This ‘full-length app-album’ is an interesting application in which studio-produced music, music apps and visual art meet.
Today is the official release of the alpha version with all the music tracks that can be bought from the free main (mother) app. The beta was published earlier this year.
[Björk website]
[iTunes link]