Android: The next time you need to meditate, relax or fall asleep, fire up Doze on your Android phone and let its relaxing sounds take over. The app has a minimalistic interface and is completely free, without any ads.
Doze lets you choose a "sleep timer" if you need one, between three, five and 10 tracks. If you don't want that, hit play and it will endlessly stream relaxing music -- a mixture of sounds of the nature (chirping birds, rain) interspersed with a light piano track, chimes, and vocals. It requires an internet connection to work.
There's no science in this like the world's most relaxing music, but it sure gets the job done without any fuss.