app. The initial sleep-tracking feature, released in 2020 (with iOS 14 and watchOS 7), included a determination of two states — asleep or awake — for each 3...

https://www.apple.com/healthcare/docs/site/Estimating_Sleep_Stages_from_Apple_Watch_Sept_2023.pdf

trackers.5,6,7 Trackers are often embedded in third-party code that helps developers build their apps. By including trackers, developers also allow third pa...

https://www.apple.com/privacy/docs/A_Day_in_the_Life_of_Your_Data.pdf