I have been shutting down Pandora using swipe-to-close to deal with its high battery usage. However, I've recently found that it's still somehow active in the background. I have my phone synced to my car's bluetooth, and when I got in the car yesterday, my phone connected and started playing music. The music in question isn't on my phone, and seems to match the Pandora station I was last listening to. I can see in Now Playing that music is indeed playing, and I can hear it, but Pandora isn't open. I also have a Pebble with the Pandora app, and that's not showing the song title, as it would were Pandora open.
I'm coming to the conclusion that somehow Pandora is running in the background, prompted by my car's connection via bluetooth, but I can't figure out how to turn it off. In the interests of prolonging battery life, I'd really like to be able to turn it off completely. Is there any way to do this short of uninstalling it? And how is it possible for the app to continue to run after force quit?