This is a pretty simple app so doesn't warrant a lengthy review, but I have been using it every night for nearly two weeks now and I believe it is significantly helping me sleep. At the time of review, this app has 20 different sounds and melodies to soothe you for a nap or for a whole nights sleep. You can independently activate as many of the sounds as you like and adjust the volume levels accordingly (I keep mine low enough so it is effectively background noise). It's quite nice figuring out which combination of sounds you are most in the mood for and at what levels. You can also set a timer to shut the sounds off after a certain period, save/load one preset (more slots for this would be an improvement), and like most applications it can run in the background as you use the phone for other tasks. My body has reacted quite well to sleeping with some of these sounds on repeat, but I think it would be even better if there were even more samples, they had longer loops, and the sound quality improved. Perhaps it's just my phone's speakers (Moto Droid), but it doesn't sound as good as an mp3. To the developer's credit, more sounds have been added since I installed and the design is more attractive. Highly recommended for the under-rested.