As is the theme with most year-end lists, AI is involved here and likely best represented via the iPad App of the Year, Moises. The name is a subtle pun at its ability to separate sounds on a track, and that makes sense as it's for musicians and producers. You can either record sessions within the app or upload files into Moises to have its AI models split instruments, including vocals, on a given track, automatically add an approximately timed metronome, or even change the key.