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.

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

Top Rated Comments

iLoveDeveloping Avatar
15 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
15 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
15 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
15 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
15 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
15 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)

Top Stories

tile sticker e1570533758981

Tile CEO: 'We Welcome Competition From Apple, But We Think It Needs to Be Fair'

Tuesday May 4, 2021 9:51 am PDT by
Just after Apple announced its AirTags, Tile CEO CJ Prober relayed his concerns about competing with Apple in the tracking space, and said that Tile would ask Congress to investigate Apple's business practices specific to Find My and item trackers. Prober this week did an interview with Bloomberg, where he further expanded on Tile's complaints about Apple and why he feels that Tile is...
signal instagram ads3

Signal Shares the Instagram Ads Facebook Doesn't Want You to See

Wednesday May 5, 2021 1:29 am PDT by
Encrypted messaging app Signal has had a series of Instagram ads blocked from the social media platform, after it attempted to show users how much data the Facebook-owned company collects about them and how it's used to push targeted ads. In a blog post, Signal described how it generated the ads to show users why they were seeing them, simply by declaring upfront the information that the...
tracking disabled ios 14 5

Analytics Suggest 96% of Users Leave App Tracking Disabled in iOS 14.5

Friday May 7, 2021 1:51 am PDT by
An early look at an ongoing analysis of Apple's App Tracking Transparency suggests that the vast majority of iPhone users are leaving app tracking disabled since the feature went live on April 26 with the release of iOS 14.5. According to the latest data from analytics firm Flurry, just 4% of iPhone users in the U.S. have actively chosen to opt into app tracking after updating their device...
fortnite apple logo 2

Epic CEO Tim Sweeney Admits App Store's 30% Cut Is Similar to Consoles, Would Have Accepted Special Deal With Apple

Tuesday May 4, 2021 1:54 pm PDT by
Apple's legal battle with Epic Games is continuing on, and during the second day of the trial, Epic Games' CEO Tim Sweeney continued his testimony against Apple. Sweeney was grilled by Apple's lawyers, and made several points seemingly favorable to Apple. In addition to mentioning how he prefers Apple's iPhone and values Apple's privacy policies that he's aiming to dismantle, Sweeney...
snapchat dark mode

Snapchat Rolls Out Dark Mode on iOS

Wednesday May 5, 2021 1:17 am PDT by
Nearly two years following the release of iOS and iPadOS 13, which included native, built-in, and systemwide dark mode, Snapchat, one of the world's most prominent social media networks, has finally rolled out a dark mode theme for iOS users. Snapchat began testing a dark mode theme of its app design late last year with a small group of iOS users. Now, Snapchat says that as of this week, it...
netflix sign up

Apple Discussed 'Punitive Measures' Against Netflix for Dropping In-App Purchases

Wednesday May 5, 2021 11:03 am PDT by
As the Epic Games v. Apple trial progresses into its third day, Apple's internal documents and communications with various companies are continuing to surface, giving us some insight into the dealings that Apple has had around the App Store. Back in December 2018, Netflix stopped offering in-app subscription options for new or resubscribing members and instead began requiring them to sign up ...
iphone 12 preorder purple

Apple Begins Transition to Randomized Serial Numbers With Purple iPhone 12

Wednesday May 5, 2021 9:17 am PDT by
MacRumors previously reported about Apple's plan to switch to randomized serial numbers for future products starting in early 2021, and this transition has now started with the new purple iPhone 12 model in multiple countries. With assistance from Aaron Zollo, host of the YouTube channel ZolloTech, we can confirm that the purple iPhone 12 released last month has a new 10-character serial...
airtag 1

AirTag Anti-Stalking Measures 'Just Aren't Sufficient' Says Washington Post Report

Wednesday May 5, 2021 6:03 pm PDT by
The safeguards that Apple built into AirTags to prevent them from being used to track someone "just aren't sufficient," The Washington Post's Geoffrey Fowler said today in a report investigating how AirTags can be used for covert stalking. Fowler planted an AirTag on himself and teamed up with a colleague to be pretend stalked, and he came to the conclusion that the AirTags are a "new means...
iphone 13 pro max dummy notch

iPhone 13 Pro Max Dummy Model Depicts Smaller Notch

Tuesday May 4, 2021 1:08 pm PDT by
Apple's iPhone 13 models are expected to feature a slimmed down notch, marking the first major change to the TrueDepth camera system since it was introduced in the 2017 iPhone X. We're still months away from the launch of the iPhone 13, but Lewis Hilsenteger of Unbox Therapy managed to get an iPhone 13 Pro Max dummy model that represents what we can expect from the new 2021 device. Dummy...
iPad Pro July Shipping

12.9-Inch iPad Pro Now Delivers as Late as Mid-July

Wednesday May 5, 2021 7:10 am PDT by
While the new 12.9-inch iPad Pro is set to launch in the second half of May, orders placed today are estimated for delivery as late as mid-July on Apple's online store in the United States — some two months later. The new 11-inch iPad Pro is faring better so far, with some configurations available for delivery in the last week of May. The new 12.9-inch iPad Pro features a Liquid Retina XDR ...