Sleep Sounds by Sleep Pillow

Sleep Sounds features a bunch of different sounds, but where it shines is in its mixes. You can create your own mixes, and the app says there are over 300,000 different combinations you can make.

Besides the huge number of sounds available, the app also features high-quality images to help you set the mood. It also comes with a couple of useful features, including a sleep timer and an alarm clock so you can go to bed and wake up feeling relaxed.