Apple Watch Series 10 leak reveals upgraded ECG sensor and new sleep apnea detection feature

We’re just a few days away from Apple’s big Glowtime event on Monday, and the rumor mill isn’t showing any signs of stopping. While the iPhone 16 line will undoubtedly be the show’s main star, we also expect the Apple Watch Series 10 (or Apple Watch X) to be revealed along with the AirPods 4. Two new leaks claim the next-gen Apple Watch will feature an updated ECG sensor capable of detecting sleep apnea. 

Sources familiar with Apple’s plans told 9to5Mac that the updated ECG/heart rate sensor is capable of delivering more accurate results, thus unlocking new features on the Apple Watch Series 10. That corroborates a Friday Bloomberg report that sleep apnea detection, a long-rumored feature that Apple’s supposedly been working on, will finally make the cut for its next line of smartwatches. 

Bloomberg’s Mark Gurman said sleep apnea detection will be a headlining feature for both the Series 10 and Ultra 3. The watches will be able to detect whether a user shows signs of sleep apnea, i.e. if their breathing repeatedly starts and stops during the night, and then recommend they consult with a doctor for further assistance.

It would presumably work similarly to how the Apple Watch currently prompts users with alerts about irregular heart rate, fluctuating blood oxygen levels, and other health conditions. Odds are the sleep apnea feature will be related to the new Vitals health app added with the watchOS 11 public beta. This app streamlines the Apple Watch’s health monitoring tools to provide a snapshot of all your key wellness metrics, which it monitors while you sleep. 

According to 9to5Mac, Apple is also shaking up how its smartwatches process the health data collected by these sensors: “This includes using new algorithms in the Health app on the iPhone to look for atrial fibrillation, rather than on the Apple Watch itself.” Whether the Apple Watch Ultra 3 gets these same improvements remains unclear, though our guess is it’s likely given Apple’s previous smartwatch launches. 

Gurman cautioned that while Apple will announce the feature on Monday, it may not be available out of the box once the new products go on sale. The functionality could come as part of a future watchOS software update. 

Better water resistance and new watch faces

An updated ECG sensor isn’t the only new feature headed for Apple’s next-gen smartwatches. 9to5Mac reports the Apple Watch Series 10 will be certified for “high-speed water sports up to 20 meters deep,” which means it could get Apple’s Depth app, currently an Apple Watch Ultra exclusive. This app monitors the time, depth, water temperature and maximum depth during each underwater session. The current Apple Watch Series 9 is water resistant up to 50 meters and not recommended for high-velocity water activities or submersion below shallow depths. 

Previous reports have suggested Apple’s bumping up the screen size for the Apple Watch Series 10, jumping to 44mm and 48mm size options from the 41mm and 45mm options on the Series 9. To take advantage of the increased display real estate, Apple’s apparently planning to introduce new watch faces, including a “Reflections” option that reacts to ambient light as well as a new Hermès option called “Regatta” that lets users start timers more easily. 

Of course, we’ll have to take all of this with a grain of salt for now. But we don’t have long to wait to hear more from Apple. In the meantime, be sure to check out how to watch the Apple Glowtime event so you don’t miss the big event.

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