I like how absurdly NIH this comes off as. Clementine is the best music player I've ever used, and it is pure qt based like Canonical wants, but hey, they don't have a CLA on it.
The only excuse is "we don't like the interface" but anything they make will have none of the features Clementine does.
On the phone, though, a music player is probably one of the most trivial apps ever with qt multimedia. That shouldn't be hard to make unless they try to get web services integrations.