I've liked the Google Play Music All Access service. $10 a month and lets you download and stream all the music you want as long as it's in their library of 20,000 songs. Also syncs with any of your other Android devices and your computer via the web. The only issue I've found is that when you download the songs to your device, it will only save them to the internal memory. I'm hoping this changes at some point because 16GB doesn't go far when it has to be used for almost everything. Right now I have a 64GB external SD card that is being used solely for storing pictures taken with the camera. Been happy with the service otherwise, though.