Better Sleep Through Sound Pink Sleep official mobile app is designed to provide users with unique sounds to assist them in both sleep and concentration. The app contains a library of Pink Sleep audio tracks, which can be customized to fit the user's needs. The tracks are based on Pink noise, which is a type of noise that is known to help people relax and fall asleep. In addition to the Pink noise tracks, the app also contains a number of other soundtracks that can be used for concentration and focus.