Just ordered an LG G Watch for a pretty solid price, but while I wait for it to arrive, is there anything that I should definitely get for it?

Functions-wise, I'm definitely using it for music; seems more convenient to play music through the watch to my Honda Civic than with my phone (plus I keep forgetting my phone since I don't put it back in my pocket once it's synced). Can I use apps like Spotify and Amazon Music as well?

How about screen protectors and the like? Any brand in particular?