I have terrible insomnia, and I troll the App Store for sounds of the one thing that drops me off to sleep: good ocean wave sounds. It is really hard to find realistic sounds. It is hard when I grew up by the sea. But this app is outstanding for its quality and number of different ocean waves that are just heavenly. And I have found some other really cool tracks that have helped lull me to sleep, too! Yes, the tracks are more costly than others, but the quality is something out of this world.