Amazing! I have had insomnia for over 35 years. Most sleep medications don't work on me  or have unwanted side effects. The Sleep Induction tone played so I can Just hear it with the background sounds turned off (which I find distracting) puts me to sleep almost every time. This app is worth it just for that One setting. I have been using all sorts of binaural CDs and apps for years. This one seems to have the best frequencies for the job. This app is the best I've found of its kind.