This Android app assumes you have already moved your Google Play Music files to your SD card and links the director back to the appropriate place. If you don't know what that means, this isn't the app for you.
This app scans through the Google Play Music database, reads the tags for the bare Play Music MP3 files, and re-tags them. This can be useful if you'd like the other audio apps on your device to be able to see those files as anything other than 12345.mp3
.