Apple released new system software for iPhone and Apple Watch on Thursday to return blood oxygen sensing to all Apple Watch users, removing a limitation that irritated many in the United States. Americans missing the feature can install iOS 18.6.1 and watchOS 11.6.1 now.
There’s also an iPadOS 18.6.1 update, but there are no fresh updates to macOS, tvOS or visionOS.
iOS 18.6.1, watchOS 11.6.1 are a boon to US Apple Watch wearers
Since 2024, Apple has been barred from selling U.S. customers new Apple Watch units with the Blood Oxygen application. Instead, it’s had to sell units with the app removed. Early on Thursday, Apple announced a workaround, and promised software updates for Apple Watch and iPhone to provide it. These are now available.
The release note for iOS 18.6.1 reads, “This update provides a new Blood Oxygen experience for users in the United States with Apple Watch Series 9 and Series 10, and Apple Watch Ultra 2. Measurements are calculated on iPhone and viewed in the Health app.”
The workaround doesn’t bring the Blood Oxygen application back to Apple Watch. Instead, it allows the iPhone to display the same data. That’s why iOS and watchOS updates are needed.
As part of our ongoing goal to help you live a healthier life, we launched a redesigned Blood Oxygen feature for Apple Watch Series 9, Series 10, and Ultra 2 users in the US today!
Download the latest software to try it out.
— Greg Joswiak (@gregjoz) August 14, 2025
The new versions, which are ready to be installed now, replace iOS 18.6, iPadOS 18.6 and watchOS 11.6 that launched July 29. They don’t seem to include any new features aside from the blood oxygen fix. That’s why it’s not surprise there are no equivalent updates for Mac other Apple computers.
How to patch your iPhone, iPad and Apple Watch
iPhone and iPad users can install the new iOS or iPadOS version directly by opening the Settings app and going to General > Software Update. Alternatively, update devices by connecting them to a Mac (or to a PC running iTunes).
The watchOS update can be installed directly onto an Apple Watch, as long as the wearable is connected to Wi-Fi. From the Settings app, navigate to General > Software Update. Or install it from an iPhone by opening the Apple Watch app and going to My Watch > General > Software Update.
