Currently, there’s no good way to listen to your favorite music apps like Spotify or Pandora while you swim or run. If you run outside, you have to carry around a huge smartphone. If you want to swim and listen to music, you’ve got to risk putting your phone in a waterproof case (that might not be 100% waterproof) and strap it to your body. The Delphin runs all the same apps as your phone on a device the size of a saltine cracker.