I got this app for meditating, since Ive used other expensive binaural CDs before, and this is so much better than those other products. But I thought that beat settings like Concentration, Headache Relief, Fear Reduction and Nasal Passages were ridiculous. Then I had a bad day-old migraine. I was in bed with shades drawn, when a friend asked if there was anything for headaches on the app I had been talking about so much. I was really angry with her for suggesting it, since I thought that those entrainment selections were just snake oil. But I set the timer to 15 minutes, I didnt want to waste my time on something that wouldnt work, and used the Headache Relief beat. My headache was about 80% better in 15 minutes, and an hour later (without listening to more beats) it was gone! Ive never had migraine relief from *anything* after Id had it for longer than 5 or 6 hours. I was amazed. Since then, Ive experienced sinus relief using the Nasal Passages beat, and stomach pains disappear with the Intestines beat. A good friend with severe fear of flying said that the Fear Reduction beat allowed her to have a comfortable flight. I was so wrong about those physical entrainments. This is powerful stuff!