Yesterday's update of Google Play Music for Android (v5.3.1316M) added external SD card support for offline music. Users who have an Android device with an SD card slot will now be able free up their device's internal storage by saving offline music files onto an external card.
The feature is only available on KitKat for now, with "experimental support on some older devices." If you have one of those devices, such as the Galaxy S4, here's how to change the offline storage location to your external card:
Go to Google Play Music's … Read more