For better sleeping habits
CBT-i Coach is an iOS-only app that was developed for soldiers suffering from PTSD-induced insomnia. But the app’s sleep tracker and relaxation exercises can help anyone establish healthy sleep routines.
Entrain helps airline passengers overcome jet lag, creating customized schedules that specify when and how long to sleep or stay awake and seek out or avoid light. For Android users, there’s Jet Lag Rooster.
Just Noise is an iOS-only white-noise generator that can help you fall asleep or eliminate distractions when you’re working.
PVT-Touch is less an aid than a diagnostic tool—a simple game that measures alertness and responsiveness and will tell you when a nap will do you good or when you’re better off pushing onward with the task at hand. It can be downloaded from a University of Washington website at depts.washington.edu/chilllab/research.