Low oxygen saturation, often indicated by a low SpO2 reading, means that there is a lower percentage of oxygen in your blood than what is considered normal for your age and health.

Fitbit recently rolled out blood oxygen monitoring on the Versa, Versa 2, Versa Lite, Charge 3, and Ionic, helping you track how well oxygen is distributed through your body during sleep.

The blood oxygen levels of the four tested climbers were startlingly low — the lowest a mere 19.1 millimeters mercury, the researchers report. In patients, levels below 60 mm Hg are cause for ...

Apple is working on a feature that will allow the Apple Watch to detect blood oxygen levels for the first time. ... and in a very generalized chart; you can’t see exact or hour-by-hour metrics.