Recently (iOS 6) I've had Genome work fine except trying to save (export) a song, you give it a name press button and crash. However, this is as of Nov 11, 2012, for all I know an update comes out tomorrow.
I've also had iFretless Bass crash on startup in iOS6 but again, could be fixed any day or its my setup (though its both iPhone and iPad versions, reinstall does nothing.
One off-topic P.S. - I still have an old iPhone 1 with a working Noise.io on it, Yea!!! (But my old iPhone 3GS is a no go, good old iPhone 1