What is the best sleep tracking app?

A useful sleep app fits your phone or wearable, shows trends clearly, and gives you control over sensitive data.

Choose one that works with your phone or wearable, explains trends clearly, and lets you export or delete your data.

What sleep trackers can and can’t tell you

Sleep apps estimate your night from movement, sound, and — with a watch — heart rate. They are good at the big picture: how long you slept, how regular your schedule is, whether you are trending better or worse. They only guess at exact sleep stages, though. Treat trends as useful and any single night’s score as entertainment.

How to choose, step by step

1. Match it to what you own. A watch or ring tracks automatically and adds heart-rate data; a phone-only app uses the microphone and motion, and must sit on your mattress or nightstand.
2. Judge it on trends, not scores: weekly averages, sleep and wake consistency, and time in bed are the numbers worth your attention.
3. Read the privacy policy first. Sleep data is sensitive — pick an app that lets you export and permanently delete your data, and check whether data is sold or shared.
4. Use the free tier for two full weeks before paying. Most people discover the useful insights are the simple ones.
5. Act on the boring finding: for most people the data points to an irregular wake time. Fixing that one habit improves sleep more than any in-app program.