Apple Watch Blood Oxygen Monitoring Feature Found in iOS 14 Code

Apple is working on a new Apple Watch feature that detects blood oxygen levels, according to newly discovered code snippets in iOS 14 (via 9to5Mac).

applewatchheartratesensor
Blood oxygen saturation naturally fluctuates throughout the day, but large variations can be linked to health issues. For example, 95-100 percent oxygen in the blood is considered normal, but a drop below that percentage could be a sign of a serious respiratory or cardiac problem.

At the center of Apple's new feature is a new health notification based on blood oxygen levels – when Apple Watch blood oxygen saturation drops below a certain threshold, the wearer is alerted, just like existing heart rate notifications.

Apple holds patents for blood oxygen monitoring, and early prototypes of the first Apple Watch featured sensors that measured blood oxygen monitoring among other biometrics, but many of these functions never made it into the final product because of consistency issues.

When the original ‌Apple Watch‌ was released back in 2015, iFixit actually discovered that Apple's heart sensors have the capability to monitor blood oxygen levels, but Apple has never activated it.

It remains to be seen whether the latest incarnation of the feature will rely on new hardware in the Apple Watch Series 6 or if it will come as a software update as part of watchOS 7, both of which are expected to arrive this year. Rumors persist that sleep tracking will also be included in the next Apple Watch model.

Other smartwatch and fitness tracker makers including Google-owned Fitbit already offer blood oxygen monitoring features in some of their devices, so Apple is playing catch-up in this regard, but that could mean the company has a more advanced implementation of the feature in the works.

Related Roundup: Apple Watch Series 8
Buyer's Guide: Apple Watch (Neutral)
Related Forums: Apple Watch, iOS 14

Top Rated Comments

iLoveDeveloping Avatar
40 months ago

It's quite illogical and stupid to wear a watch or iWatch for analyzing sleep behavior.
Are you serious??? Really? ? Tons of people want this! This is one of the reasons I have used Fitbit for years and still haven’t gone to Apple Watch! If they implemented this, I’d buy it right away!!
Score: 12 Votes (Like | Disagree)
nitramluap Avatar
40 months ago

It can be added to a Series 5 with an OS update. Apple Watches have had the hardware to measure it for years. The problem is accuracy. If Google/Fitbit are now doing it, it looks like accuracy is reliable enough now that Apple is willing to implement it.
Actually, this is false.

In order to measure SpO2 you require a red & infrared LED array - not green & infrared. Green LEDs are very good at detecting a pulsatile flow of a red substance (ie. Blood) even in tricky situations where there is lots of movement; red, not so much. This is why most fitness trackers use green LEDs for pulse rate detection during workouts.

A pulse oximeter needs a red & infrared LED due to the unique characteristics of the difference between the absorption spectra of oxygenated haemoglobin & deoxygenated haemoglobin at very specific light frequencies - which just happen to be red (660nm) & infrared (940nm).

Unless the old hardware has a dormant red LED which I’m pretty sure it doesn’t, this will require new hardware. But I would also question the need for it for the general public, unless it is coupled with sleep monitoring.

Disclosure: I’m an Anaesthesiologist (and an Apple Developer ;)).
Score: 8 Votes (Like | Disagree)
PickUrPoison Avatar
40 months ago

Not to say it's a bad thing, but wearing a smartwatch or iWatch isn't an intuitive approach for sleep analysis.
Are you sure? I’ve heard it’s quite illogical and stupid...
Score: 7 Votes (Like | Disagree)
m.x Avatar
40 months ago
While I hope this feature will be available for Series 4 watches, the more interesting part of this article is that 9to5mac got their hands on a part of iOS14. Is there more to come?
Score: 7 Votes (Like | Disagree)
shinkansenwarrior Avatar
40 months ago
Sp02 monitoring is the one thing that I felt was missing to make the iWatch a complete product IMO.
Let's hope this feature becomes available and I hope it can measure blood/oxygen levels accurately.
I am looking forward to seeing this.
Score: 7 Votes (Like | Disagree)
nexu Avatar
40 months ago

Not necessarily. The feature may require a new sensor or other hardware in the upcoming Series 6.
Knowing Apple, they’ll make it series 6 exclusive even if it’s technically possible on series 5
Score: 6 Votes (Like | Disagree)

Popular Stories

iOS 17 on Phone Feature

Gurman: iOS 17 to Provide Several 'Most Requested Features'

Sunday March 26, 2023 6:05 am PDT by
Apple changed the strategy for iOS 17 later in its development process to add several new features, suggesting that the update may be more significant than previously thought, Bloomberg's Mark Gurman reports. In January, Gurman said that iOS 17 could be a less significant update than iPhone updates in previous years due to the company's intense focus on its long-awaited mixed-reality...
dynamic island

iPhone 15 Dynamic Island to Include New Integrated Proximity Sensor

Friday March 24, 2023 12:27 am PDT by
This year, all iPhone 15 models will include Apple's Dynamic Island that unifies the pill and hole cutouts at the top of the display, but there will also be a material change to the feature that wasn't included in the iPhone 14 Pro models. According to a new tweet by Apple industry analyst Ming-Chi Kuo, the proximity sensor on the iPhone 15 series will be integrated inside the Dynamic Island ...
top stories 25mar2023

Top Stories: iPhone 15 Pro Design Leak, iOS 16.4 Coming Soon, and More

Saturday March 25, 2023 6:00 am PDT by
We're still almost six months away from the official unveiling of the iPhone 15 lineup, but it seems like every day we're learning more about what to expect from the next-generation models. Notably, this week gave us our clearest look yet at what appear to be some changes for the volume and mute control hardware. iOS 16.4 and associated releases are also right around the corner with some new ...
Hero0009

Best Apple Deals of the Week: Samsung's Smart Monitor M8 Gets Massive $250 Discount, Along With Year's Best AirPods Prices

Friday March 24, 2023 10:23 am PDT by
We saw a lot of great deals on Apple products and related accessories this week, including Samsung's iMac-like Smart Monitor M8 for $250 off, a 30 percent off spring sale at Anker, and the year's best prices on numerous AirPods models. All of these deals are still available to purchase right now, so we're recapping them and more below. Note: MacRumors is an affiliate partner with some of these ...
Steve Jobs Theater dusk

Apple Reportedly Demoed Mixed-Reality Headset to Executives in the Steve Jobs Theater Last Week

Sunday March 26, 2023 5:53 am PDT by
Apple showcased its mixed-reality headset to the company's top 100 executives in the Steve Jobs Theater last week, according to Bloomberg's Mark Gurman. In the latest edition of his "Power On" newsletter, Gurman explained that the "momentous gathering" is a "key milestone" ahead of the headset's public announcement planned for June. The event was intended to rally Apple's top members of...
apple mixed reality headset concept by david lewis and marcus kane

Some Apple Employees Seriously Concerned About Mixed-Reality Headset as Announcement Draws Closer

Sunday March 26, 2023 8:25 am PDT by
Some Apple employees are concerned about the usefulness and price point of the company's upcoming mixed-reality headset, The New York Times reports. Apple headset concept by David Lewis and Marcus Kane Initial enthusiasm around the device at the company has apparently become skepticism, according to eight current and former Apple employees speaking to The New York Times. The change of tone...
iphone 14 pro max deep purple feature purple

iPhone 15 Pro Rumor Recap: 10 New Features and Changes to Expect

Thursday March 23, 2023 6:42 am PDT by
While the iPhone 15 series is still around six months away from launching, there have already been plenty of rumors about the devices. Many new features and changes have been rumored for the iPhone 15 Pro and iPhone 15 Pro Max in particular. Below, we have recapped 10 changes rumored for iPhone 15 Pro models that are not expected to be available on the standard iPhone 15 and iPhone 15 Plus:A1...
iOS 16

iOS 16.4 Will Add These 8 New Features to Your iPhone

Sunday March 26, 2023 8:06 am PDT by
Following nearly six weeks of beta testing, iOS 16.4 is expected to be released to the public as soon as this week. The software update includes a handful of new features and changes for the iPhone 8 and newer. To install an iOS update, open the Settings app on the iPhone, tap General → Software Update, and follow the on-screen instructions. Below, we have recapped eight new features and...