The Apple Watch doesn’t come with its own sleep tracking app, no matter which model you buy. Nor does Apple advertise “sleep tracking” as one of its features. The reason is battery life. Apple’s unspoken assumption is that you will be recharging your Apple Watch’s “all day” battery overnight.

Of course, if you want your Apple Watch to track your sleep — you can. There are plenty of third-party apps that track sleep that you can download. These apps are able to track how long and how well you sleep.
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