Free Up Space for Android Phones when Syncing Spotify
Although you can sync up to 3,333 Spotify tracks in Offline mode to up to three devices, plus all your local files, transferring a large chunk of these files on to your phone may cause it to quickly fill up.
The good news for Android users is that their phones use external memory cards (much like the memory cards in digital cameras), and you can buy high-capacity ones to store a greater number of tracks in Spotify’s cache. Consider yourself lucky that you don’t need to worry too much about your cache reaching its capacity or having to resync your phone every other day with fresh tracks.
Point your cache to your memory card by following these steps:
Clear your Spotify settings by choosing More→Settings→Clear Saved Data.
Log out of Spotify by choosing More→Logout, and then tapping OK when asked if you’re sure.
Tap the Spotify icon to restart the app.
When the login screen appears, press your phone’s Menu key.
Select SD Location from the menu that appears.
Enter the path to the location of your card in the text box that appears.
For example, enter /mnt/sdcard. The exact location varies from phone to phone.