Maybe I'm the only one, but I constantly play music in friend's cars, and depending on the group and mood, I pick and choose from various playlists. BUT... Every friggin time, I accidentally tap outside the tiny ... circle button. This results in an angry group and a bad car DJ. Solution: create a queue or jukebox mode so anything I tap is added to the queue instead of played immediately.
This would also be great at parties. Set up spotify on my iPad, and as people search for music it doesn't stop the current track. This would save tons of unsatisfied groups.