Does using music on iphone use data?

Does using music on iphone use data?

Using doesn't affect it but its the amount of songs you have on your iPhone.

Only if you're on an app or online

Depends.

If you are using music that you synced from iTunes onto the iPhone, then no.
If you are using music via iTunes Match/Pandora/Spotify, then yes (if not on a Wi-Fi connection)