iOS 18.6.1 Just Dropped—And Apple Changed How Blood Oxygen Works on iPhone and Apple Watch. Find out what’s new, supported devices, and how to update.
Introduction
iOS 18.6.1 Just Dropped—And Apple Changed How Blood Oxygen Works. Apple brings back the feature with a twist—see how it now runs on your iPhone. Apple is yet to update another iPhone, and it comes with a turn. On Thursday, the company released iOS 18.6.1, a new update that explains how blood oxygen features work on some Apple Watch models. If you have found the right equipment, things are going to look a little different in your health app.
What is new in iOS 18.6.1?
Honestly, it is not a feature-packed release—but it is still an important one. Apple says that the main attraction of iOS 18.6.1 is a redesigned blood oxygen experience. Instead of being calculated on your Apple Watch itself, oxygen readings are now directly processed on your coupled iPhone. You will get results in the respiratory section of the health app.
Recently, the change for the US customs was made possible by the ruling, which approved Apple to bring back the convenience in a new form.
Apple Watch update also
If you are the owner of an Apple Watch Series 9, Series 10, or Apple Watch Ultra 2, you also want to grab the watchOS 11.6.1. This partner update unlocks the new blood oxygen setup on your watch.
But the heads-up—if your watch is old, or if you bought it outside the U.S., nothing is changing. Those models will still run the original version of the convenience (if they had it exactly).
Which iPhones can run iOS 18.6.1?
Good news: You do not need the latest iPhone 16 to use this update. Every iPhone is supported since 2018. This includes:
iPhone XS, XS Max, and XR
iPhone SE (Second and 3rd Generation)
Each iPhone from the 11 through the iPhone 16, including the brand-new iPhone 16E
On an iPhone 16 Pro Max, the update size is about 720 MB, and it took only 10 minutes to download and install.
Why Apple changed it
If you are wondering why the blood oxygen app required a makeover, then there is a backstory: Apple had to disable the feature in January 2024 after a legal battle with a medical device company, Masimo. This is the clever work chart of the Apple redesign that withdraws the feature for American users without violating the patent.
How to update
It is easy to update:
Go to settings.
Tap General.
Choose software updates.
Now hit the update and follow the signals.
Your watch works in the same way through the updated watch app.
Apple calls it a “medium-sized update,” but it is a very big thing for anyone who missed the blood oxygen feature. And if history is a clue, more tweaks are on the way.
Conclusion
iOS 18.6.1 may not look like a massive update on paper, but for Apple Watch owners in the U.S., it’s a game-changer. By cleverly moving blood oxygen calculations to the iPhone, Apple has brought the feature back, overcoming legal hurdles.
If you are the owner of the recent iPhone and Apple Watch, this update is worth establishing – if you are missing your blood oxygen reading, it is quick, simple, and necessary. And Apple already seems to be cool before the hurricane of iOS 18.6.1 large updates, with more features in iOS 26 at the end of this year.
People also ask
Q 1. Is iOS 18.6.1 Worth Updating?
Q 2. Which iPhones support iOS 18.6.1?
Since 2018, all iPhones—iPhone XS, XR, SE (2nd & 3rd GEN), and iOS 18.6.1, including the full iPhone 11 through the iPhone 16 lineup.
Q 3. Does the blood oxygen update work on all Apple Watches?
No, the new setup works only on Apple Watch Series 9, Series 10, and Apple Watch Ultra 2. Older U.S. models or watches purchased outside have not been affected.
Q 4. Why did Apple redesign the blood oxygen feature?
Apple had to disable the feature in early 2024 due to a patent dispute with Masimo. This redesign, which shifts calculations to iPhone, is Apple’s workaround.