Apple Watch may get built-in sleep tracking by 2020
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Since its launch in 2015, Apple has increasingly positioned the Apple Watch as a health and fitness device; something that helps users track their workouts and look after their body. But one popular feature has been missing from Apple’s built-in software: sleep-tracking.
from https://www.theverge.com/2019/2/26/18241136/apple-watch-sleep-tracking-functionality-2020-report
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