A free program for Android, by Seebs LLC.
It is a very simple and intuitive application that makes it possible to experience the beauty of rainbows and soft bells in your smartphone.
This app is based on the idea that people with autism, as well as people who are just sensitive to noise, find it soothing to experience the sounds of raindrops and bells. This application is based on the same concept and provides the same experience that a person with autism would have.
The first time you open the application, it will make a bit of noise and draw a bunch of lines, squares, and hexes. After that, it should have a guess as to how fast your device is, and be able to perform decently. This is a little unreliable still; improvements are planned.
