eracode:NonprayingMantis: it's probably a 6+, not a 6S (people are shocking with model numbers)
Just tell them to get spotify and be done with it. No need to have a music library taking up room on the phone when you can just stream whatever you want whenever you want.
.... except for when there's no wifi or data available - eg on a plane? Or if there's no wifi and you don't want to spend data on streaming for some reason. I keep a heap of music on my iPad and Android phone for emergencies/unusual situations - but admittedly hardly ever use it because streaming.
You can download spotify tracks and play them when offline.

