Apple today announced that it would release an iPhone update — and it’s one that nobody had been expecting. The surprise release is for U.S. iPhones only, and concerns a missing feature on the Apple Watch.
Which iPhones Can Run iOS 18.6.1?
The new iOS 18.6.1 software is compatible with all iPhones from 2018 onwards. That means the iPhone Xs, iPhone Xs Max and iPhone Xr and all iPhones since, including the iPhone SE in both its second- and third-generation models. And all members of the iPhone 16 series are included, right up to the iPhone 16e. However, it will only appear on U.S. iPhones, it seems.
How To Get It
When it arrives, likely around 10 a.m. Pacific today (Aug. 14, 2025) you download it like this: open the iPhone Settings app, then choose General, followed by Software Update. Next, click on Download and Install, and it’ll be on your phone shortly.
iOS 18.6.1 — What’s In The Release
This is a unique situation: Apple doesn’t announce when it’s releasing new software ahead of time. And because it’s not out yet, there are no release notes to study.
What is clear is that this update “will introduce a redesigned Blood Oxygen feature for some Apple Watch Series 9, Series 10, and Apple Watch Ultra 2 users through an iPhone and Apple Watch software update coming later today,” as Apple announced on its Newsroom site in the last few hours.
There may be additional security updates, bug fixes and other elements but for now all we know is that it’s designed to make millions of U.S. Apple Watch users happy.
The absence of the blood oxygen monitoring feature was because of a legal dispute between Apple and medical technology company Masimo. This redesigned feature seems to avoid the dispute. “This update was enabled by a recent U.S. Customs ruling,” Apple says.
There’s also an update for those Apple Watch models the company mentions, but for the data to be read on the user’s companion iPhone, the latest software is necessary.
You can read more about the changes to Apple Watch, and why it’s important, here.
I’ll update this post as soon as the release goes live.
