Scape is the third collaborative project between Brian Eno and musician and developer Peter Chilvers (the other two, Bloom and Trope, were also about making music on the iPad).
The app is a collection of backgrounds, shapes, patterns and colors; the user can combine them as he sees fit, and different combinations actually make music.
There are about 80 elements in all – but they all appear as the user creates the music for as long as it takes. In addition to a gallery with your own tracks, Scape has 8 examples from Eno and Chilvers – and several playlists in the same vein.