Apple Watch just keeps getting better — 9to5Mac recently discovered via iOS 14 code snippets that the next Apple Watch might be able to detect bloody oxygen levels.
This is a feature that can prove to be very useful — being able to know your bloody oxygen levels can help warn you of health conditions, preventing delayed detection of health problems.
While the Apple Watch Series 6 will probably be able to detect blood oxygen levels, it is highly unlikely that the current versions will have this feature. This is under the assumption that new hardware is needed for the feature to be integrated into the watch. However, it is believed that the built-in heart rate monitor can already ensure blood oxygen levels, so perhaps Apple only needed a software upgrade to introduce this feature.
On the other hand, Fitbit already has a built-in SpO2 sensor on some of its devices. You can check your estimated oxygen variation to monitor health conditions such as sleep apnea and asthma.
