So I dont usually write reviews, but I decided that this app deserved one. I set the timer for four hours every night and fall asleep to the sound of rain and thunder. It doesnt always increase dream frequency or intensity, but as an active dreamer who has experimented with lucid dreaming, I have noticed a difference. When it does work, it works very well and even when it doesnt, its still nice to go to sleep to. I highly recommend it for anyone who is interested in this type of thing.