Does Apple Watch know when you sleep?

Related questions

1. Is Apple watch accurate?
2. Can you Facetime on Apple Watch?
3. What is a apple watch used for?
4. Is Apple Watch better than Fitbit?
5. Is Apple watch time accurate?
6. Is Apple Watch Series 4 worth it?
7. Is Apple Watch 4 waterproof shower?
8. Are Apple watches worth the money?
9. Can you sync an Apple watch to an iPad?
10. Is Apple watch worth buying?

Tags

1. #store
2. #track
3. #sleepwatch
4. #tracking
5. #apple
6. #feature
7. #automatic
8. #baked
9. #available
10. #simply
11. #sleep
12. #download
13. #watch