Consumer-grade sleep trackers are still not up to par compared to polysomnography.
Kyubo KimDo-Yang ParkYong Jae SongSujin HanHyun Jun KimPublished in: Sleep & breathing = Schlaf & Atmung (2021)
Most of the applications tested in this study showed poor validity, while wearable devices mildly correlated with PSG. An effective use for these devices may be as a tool to identify the change seen in an individual's sleep patterns on a day-to-day basis, instead of as a method of detecting absolute measurements.