iPhone: There are all kinds of ways to discover new music these days, but if you prefer a more active approach, Endo makes finding new music as easy as doing Tinder-esque swipes.
The idea here is pretty simple: Enso gives you previews of songs, then you swipe left on the songs you hate and right on the songs you like. You can then connect Enso to Spotify to listen to full songs or check out the entire song on YouTube. It's certainly a more active music discovery process than something like Spotify's (awesome) Discover Weekly playlist, but for those who like to dig stuff up for themselves, it's a fun distraction.
Enso (Free) [iTunes App Store]