Shut Up, Brain
4 Hours of Deep Brown Noise for Sleep

It's four hours of brown noise and nothing else. Put it on when your head won't shut up. It works on a night bus as well, with the phone on your lap. There's no talking and no music, and the sound stays the same the whole way through. Headphones are good, and a speaker works too. It's on Kwalia Bliss, along with Neurutron and three more Shut Up titles.