Official Apple Watch Sleep app accidentally mentioned in Alarms app screenshotOct 15, 2019
As spotted by a MacRumors reader, the App Store screenshots for the Alarms app for Apple Watch includes text that alludes to an as-yet-unannounced Sleep app. References to Apple Watch sleep tracking features were found during the iOS 13 beta cycle, but Apple did not ship the functionality this year.
This screenshot is yet another confirmation that Apple is indeed developing a first-party Sleep app.
The UI shown in the screenshot includes a toggle for a Wake Up bedtime alarm. Bedtime alarms can currently be set on the iPhone or iPad, but are not exposed on the Apple Watch itself. It seems like the unreleased Sleep app would bring that feature over as part of a comprehensive sleep tracking system.
Ahead of iOS 13 being announced, Bloomberg reported that a Sleep Mode was coming to iOS. The publication later said that the feature was removed ahead of the public June beta builds.
Apple added its first-party Watch apps to the store because you can now delete stock apps in watchOS 6, and the App Store serves as the location to re-download them later. Apparently, someone at Apple didn't realize that the Alarms app screenshots included references to the pulled Sleep features.
For the time being, Apple Watch users have to rely on third-party apps like Sleep++ or AutoSleep.
Apple is clearly working on a first-party sleep tracking solution for its wearable, but it seems like it won't be launching until late 2020, potentially tied to new Apple Watch hardware.
In fact, the Apple Watch Series 5 battery life is weaker than previous generations. This actually makes it more awkward to use sleep tracking apps from the App Store compared to the experience of older watches; the Series 3 and Series 4 could comfortably last the night between charges... the Series 5 struggles to do the same thing.