Sleep Tech Lab | Tracker Accuracy Notes https://sleeptechlab.com Independent data and lab methodology for wearables and nearables. en-us Apple Watch Ultra 2 Accuracy Results https://sleeptechlab.com/wearables/apple-watch-ultra-2/ Lab test results for the Apple Watch Ultra 2 sleep staging algorithm compared against EEG baseline. Mon, 02 Sep 2024 12:00:00 GMT Why Deep Sleep Tracking Fails https://sleeptechlab.com/methodology/deep-sleep-tracking/ A clinical look into why consumer PPG sensors struggle to differentiate N2 from N3 slow-wave deep sleep. Fri, 30 Aug 2024 12:00:00 GMT