The Blood Oxygen app, available on Apple Watch Series 6 or later, allows you to measure the blood oxygen saturation levels directly from your wrist. With the blood oxygen sensor on the Apple Watch, this app provides insights into how well your body is absorbing oxygen and overall wellness.

One of the main features of the Blood Oxygen app is the ability to take on-demand blood oxygen measurements. This is especially helpful for individuals who want to monitor their oxygen levels regularly or have specific health concerns. Additionally, the app performs periodic background measurements throughout the day and even while you sleep if you wear your Apple Watch to bed.

All the measurements taken by the Blood Oxygen app are stored in the Health app on your iPhone. This allows you to easily access and review your data. The Health app provides the ability to filter and view measurements taken while you were asleep or in a high-elevation environment.

Please note that the Blood Oxygen app is not supported by Apple Watch SE.