Napster users can switch storage of your offline tracks from internal storage to your SD (secure digital) card.
Ensure a place for saved songs exists, or make one using a file manager.
1) Open the Napster Android app
2) Tap settings in the upper right corner
3) Tap Downloads
4) Tap Choose Music Download Location
5) Choose music location as "External".
Check out our Android app How-To Guide for more cool stuff.