For audio production, iMaschine is a fantastic app and the main reason I stay with iOS. In fact, the $5 app was so good that I ended up buying the $200 Maschine

For audio production, iMaschine is a fantastic app and the main reason I stay with iOS. In fact, the $5 app was so good that I ended up buying the $200 Maschine hardware controller + desktop software for the seamless integration: create a track in iMaschine and it will export a file that you can open up on the desktop to apply advanced effects, additional voices, etc.