Sleep Cycle is a sleep tracking app from Gothenburg, Sweden, first released in 2009. The company is listed on Nasdaq Stockholm.
The phone's microphone listens to movement and sounds through the night to estimate sleep phases. The smart alarm wakes the user within a set window when they are in their lightest sleep, which many find less groggy than a fixed alarm. The app also records snoring and sleep talking, gives a sleep quality score and shows trends over weeks and months.
The basic alarm and tracking are free. Premium adds detailed statistics, snore recordings, sleep aids and more.