Why the Blood Oxygen Feature’s Return to Apple Watch Matters
Following a legal dispute, Apple is bringing SpO2 monitoring back to its newer Apple Watch models in the U.S. The move comes as the tech giant pushes further into health and wellness
Apple Watch users in the United States will once again be able to access blood oxygen monitoring. Through a software update that recently rolled out, Apple has reintroduced the redesigned Blood Oxygen app for Series 9, Series 10 and Apple Watch Ultra 2 users who previously lost access due to an import ban.
The redesign has shifted how the watch handles SpO2 readings: sensor data is now measured on the watch but calculated on the paired iPhone, with results available in the Respiratory section of the Health app. Apple Watch models purchased outside the U.S., or those that originally included the feature, are unaffected by these changes.
What Is Blood Oxygen Monitoring?
Blood oxygen monitoring, also known as SpO2 tracking, measures the percentage of oxygen carried by red blood cells from the lungs to the rest of the body. A normal reading typically falls between 95–100%. While not a substitute for clinical testing, SpO2 tracking offers valuable insights into overall respiratory and cardiovascular health.
For everyday users, blood oxygen levels can show how the body is adapting during sleep, exercise, or at altitude. For athletes, the data can be even more practical. A steady SpO2 reading during long runs, high-intensity training, or recovery can provide reassurance that the body is oxygenating efficiently. At altitude, dips in blood oxygen saturation can reveal how well the body is acclimating. Runners and endurance athletes often cross-reference SpO2 with VO2 max, heart rate and recovery metrics to build a fuller picture of performance and readiness.
The Legal Landscape
The return of the feature comes after Apple faced a 2023 ruling from the U.S. International Trade Commission (ITC), which sided with medical technology company Masimo in a patent dispute. The decision forced Apple to disable the blood oxygen app on certain models sold in the U.S., even as the feature remained available globally.
The redesigned system represents Apple’s workaround, reportedly structured to avoid infringing on Masimo’s patents. A recent U.S. Customs ruling cleared the way for Apple to reintroduce the feature.
The reintroduction of SpO2 monitoring is significant for Apple’s position in the wearable health market. First introduced with the Apple Watch Series 6 in 2020, its absence in U.S. models created a gap compared to international versions. While the legal battle with Masimo remains unresolved, this update provides U.S. users similar access to important health data compared to their international peers.
Apple’s Big Health Push
The return of blood oxygen monitoring is part of a larger health and fitness strategy from Apple. This summer, Apple Fitness+ partnered with FuturHealth, a GLP-1 weight-loss solutions provider, to give members complimentary access to Apple’s library of workouts and meditations.
At the tech giant’s annual Worldwide Developers Conference in June, the company unveiled watchOS 26, introducing a redesigned Workout app, smarter audio integration and Workout Buddy, an AI-powered coaching tool that offers spoken encouragement based on real-time metrics. Apple Fitness+ also released new “Ready-made Custom Plans” tailored to user goals.
Apple was also reportedly developing an AI-powered health coaching service, codenamed Quartz, that would provide personalized suggestions for exercise, diet and sleep based on Apple Watch and iPhone health data.