Popular Science: Magazine reviews some of the most popular sleep tracking apps that interpret data about the movements and noises you make while you’re sleeping.

Sleep as Android: Few sleep-tracking apps are as comprehensive as Sleep as Android. In addition to actually tracking your slumber, it can help you doze off with the sounds of nature, identify the optimum point in your body’s circadian rhythms to wake you up gently, record your snoring and sleep talking, and connect to a host of third-party apps and devices (from Google Fit to the Samsung Galaxy Watch).

At the center is sleep tracking. To assess how restful your sleep is, your phone uses its built-in accelerometer, then runs algorithms and statistical analysis to split your slumber up into deep and light periods. Every morning, you’ll be able to see how many hours of sleep you got, plus how well you slept, in the form of a score.

Pillow: One of the more polished sleep-tracking apps we’ve come across, Pillow can work with an Apple Watch or just an iPhone placed on the bed. It analyzes your movements through the night to record how long you’ve been sleeping for and splits your sleep into three categories: light, deep, and REM.

Sleep Cycle: Keep your mobile device on your bed overnight, and this platform will give you access to a wealth of information about your sleeping habits. The next morning, you can see your periods of wakefulness, and light and deep sleep, which you can measure over time.

Get the full story at popularscience.com.