When I got into binaural beats I looked for apps that could help me experiment and find out what was good. This is literally the app that did that, and helped me find my personal frequencies, like the fact that 2.5 is my best delta and low tones work best for me. It is the most customizable generator that I have seen yet, and I also have to commend the developer for the voiceover accessibility. In recent updates, the place where you type in the numbers has become less accessible, but it is still usable, and it is great. I was getting sick of apps that simply gave you a bunch of tracks. If I wanted tracks, I could get a CD. I like this much better.