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With the iOS 18.6.1 and watchOS 11.6.1 updates, Apple has reactivated a key health feature: blood oxygen monitoring. This feature was unavailable on the Apple Watch in the US for more than a year and a half. With the new software, owners of an Apple Watch Series 9, Series 10, or Apple Watch Ultra 2 can once again measure their blood oxygen levels. This move follows a decision by the US Customs and Excise Service.
Blood oxygen monitoring is one of the most popular health features on the Apple Watch. It not only supports sports and fitness apps but also provides medically relevant data. The fact that it was disabled in the US for such a long period was related to a legal dispute between Apple and the medical technology company Masimo. With the new updates, the feature is back – with slight technical changes, but still usable.
The background to the patent dispute
The dispute began in 2020 when Masimo accused Apple of misappropriating trade secrets and infringing ten patents related to blood oxygen measurement. Masimo also accused Apple of deliberately poaching employees and integrating confidential technology into the Apple Watch without acknowledgment. To continue selling the smartwatches in the United States, Apple disabled the blood oxygen function via software. This measure remained in effect during the appeals process and resulted in users being denied blood oxygen measurement for over 18 months.
Decision of the US Customs Authority
The company previously stated that the feature's reavailability was made possible by a decision by the U.S. Customs and Excise Service. Based on this decision, the iOS 18.6.1 and watchOS 11.6.1 software updates were released.
Technical implementation of the new measuring function
Blood oxygen measurement now works in two steps. First, the Apple Watch records the sensor data. Then, the analysis is no longer performed exclusively on the watch itself, but on the paired iPhone. The results appear in the "Respiration" section of the Health app. The update applies only to Apple Watch Series 9, Series 10, and Apple Watch Ultra 2 sold in the US. Devices purchased and activated before the original sales ban are not affected by this feature.
Comeback of a core function of the Apple Watch in the USA
With the release of iOS 18.6.1 and watchOS 11.6.1, Apple is bringing back blood oxygen monitoring to current Apple Watch models in the US. The feature, which was disabled for a year and a half due to a patent dispute, is now available again – now with a technical adjustment that allows the data to be calculated on the iPhone. This is an important step for Apple to position the Apple Watch as the leading wearable in the health sector. Time for fresh accessories? Visit our Amazon Storefront and discover a wide selection of products from leading manufacturers, including HomeKit-compatible ones! (Image: Apple)
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