Apple Releases watchOS 5.3 With Walkie-Talkie Bug Fix, ECG Support for Canada and Singapore

Apple today released watchOS 5.3, the seventh update to the watchOS 5 operating system that runs on modern Apple Watch models. watchOS 5.3 comes more than a month after the launch of watchOS 5.2.1, a minor update that expanded ECG availability.

watchOS 5.3 can be downloaded for free through the dedicated Apple Watch app on the iPhone by going to General -> Software Update. To install the new software, the Apple Watch needs to have at least 50 percent battery, it needs to be placed on a charger, and it needs to be in range of the ‌iPhone‌.

iphone apple watch ecg
No new features were discovered in watchOS 5.3 during the beta testing process, but according to Apple's iOS 12.4 release notes, the new update, along with iOS 12.4, fixes a major bug in the Walkie-Talkie app that could allow it to be used to spy on people and it once again makes the Walkie-Talkie app accessible.

The watchOS 5.3 update also brings ECG support and irregular heart rhythm notifications to Apple Watch Series 4 owners in both Canada and Singapore. The ECG feature's launch in Canada comes a few months after Apple confirmed that it was working to bring ECG functionality to the Apple Watch in Canada "as quickly as possible."

Health Canada initially approved the ECG app and irregular heart rhythm notifications on Apple Watch Series 4 in May. ECG capabilities are now available in more than 25 countries, following the feature's rollout to many European countries earlier this year. A list of countries where ECG functionality is available can be found on Apple's Apple Watch feature availability website.

Apple's full watchOS 5.3 release notes:

This update includes new features, improvements and bug fixes and is recommended for all users:
- Provides important security updates including a fix for the Walkie-Talkie app
- ECG app on Apple Watch Series 4 now available in Canada and Singapore
- Irregular heart rhythm notifications now available in Canada and Singapore

watchOS 5.3 may be one of the final updates to the watchOS 5 operating system as Apple shifts its focus to watchOS 6, which is currently being beta tested ahead of a planned fall release.

Related Roundup: Apple Watch 10
Tag: ECG
Buyer's Guide: Apple Watch (Caution)

Popular Stories

Apple CarPlay Ultra instrument cluster themes 01

Apple's CarPlay Ultra Is Here – Does Your iPhone Support It?

Thursday May 15, 2025 5:17 am PDT by
Apple's recently announced CarPlay Ultra promises a deeply integrated in-car experience, but not all iPhone users will be able to take advantage of the new feature. According to Apple's press release, CarPlay Ultra requires an iPhone 12 or later running iOS 18.5 or later. This means if you're using an iPhone 11, iPhone XR, or any older model, you'll need to upgrade your device to access...
Apple CarPlay Ultra instrument cluster themes 01

Apple's 'CarPlay Ultra' Experience Now Available

Thursday May 15, 2025 5:07 am PDT by
Apple today announced that its next-generation CarPlay experience, now dubbed "CarPlay Ultra" begins rolling out today, starting with Aston Martin vehicles. Subscribe to the MacRumors YouTube channel for more videos. CarPlay Ultra is now available with new Aston Martin vehicle orders in the U.S. and Canada. It will also be available for existing models that feature the brand's next-generation ...
iPhone 17 Air Pastel Feature

iPhone 17 Air Battery Capacity and Weight Allegedly Revealed

Monday May 19, 2025 2:22 am PDT by
Apple is expected to launch an all-new ultra-thin iPhone 17 Air later this year, and while there have been plenty of rumors about the camera's overall design and thinness, we haven't heard any details about the device's weight and battery capacity until now. According to the leaker going by the account name "yeux1122" on the Korean-langauge Naver blog, the 6.6-inch iPhone 17 Air has a weight ...
CarPlay Ultra Climate Controls

Apple Says These Vehicle Brands Plan to Offer All-New CarPlay Ultra

Thursday May 15, 2025 8:13 am PDT by
Apple today announced the launch of CarPlay Ultra, the long-awaited next-generation version of its CarPlay software system for vehicles. CarPlay Ultra features deep integration with a vehicle's instrument cluster and systems, built-in Radio and Climate apps, customizable widgets, and more. The interface is tailored to each vehicle model and automaker's identity, and drivers can also adjust...
iOS 18 Siri Personal Context

Apple Will Reportedly Be More Cautious About Announcing New Features Well in Advance

Sunday May 18, 2025 2:50 pm PDT by
Apple plans to mostly stop announcing new features more than a few months before they are ready to launch, according to Bloomberg's Mark Gurman and Drake Bennett. The pair of reporters revealed this noteworthy tidbit towards the bottom of a lengthy report about Apple's artificial intelligence shortcomings today. This alleged change in strategy comes after Apple was forced to delay its more...
Apple Intelligence General Feature

Report: Apple's Next-Gen Version of Siri Is 'On Par' With ChatGPT

Monday May 19, 2025 9:00 am PDT by
Apple has big plans to improve Siri over the next few years, Bloomberg's Mark Gurman and Drake Bennett report. Some Apple executives are now reportedly pushing to turn Siri into a true ChatGPT competitor. A next-generation, chatbot version of Siri has reportedly made significant progress during testing over the past six months; some executives allegedly now see it as "on par" with recent...

Top Rated Comments

realtuner Avatar
76 months ago
Finally ECG in Canada. :)
Score: 7 Votes (Like | Disagree)
GtrDude Avatar
76 months ago
Would like to see them work on the communications between the phone and watch instead of only adding new features.
"Mirror Phone" is anything but...
Score: 3 Votes (Like | Disagree)
deathnite Avatar
76 months ago
ECG app is now at version 1.18.

watchOS 5.1.2 ('https://www.macrumors.com/2018/12/06/watchos-5-1-2-released-with-ecg-app/'): ECG app v1.1 ('https://forums.macrumors.com/threads/apple-releases-watchos-5-1-2-with-ecg-new-infograph-complications-and-walkie-talkie-control-center-toggle.2159056/page-9#post-27230555') (initial US release)
watchOS 5.1.3 ('https://www.macrumors.com/2019/01/22/apple-releases-watchos-5-1-3/'): ECG app v1.2 ('https://forums.macrumors.com/threads/apple-releases-watchos-5-1-3-with-bug-fixes-and-performance-improvements.2166340/page-2#post-27023412')
watchOS 5.2.0 ('https://www.macrumors.com/2019/03/27/apple-releases-watchos-5-2/'): ECG app v1.10 ('https://forums.macrumors.com/threads/apple-releases-watchos-5-2-with-ecg-functionality-in-europe-and-hong-kong-airpods-2-support.2175299/page-4#post-27229174') (available in Europe and Hong Kong)
watchOS 5.2.1 ('https://www.macrumors.com/2019/05/13/apple-releases-watchos-5-2-1/'): ECG app v1.13 ('https://forums.macrumors.com/threads/apple-releases-watchos-5-2-1-with-ecg-functionality-for-additional-european-countries.2181139/#post-27359803') (additional ('https://en.wikipedia.org/wiki/WatchOS#watchOS_5.x') European countries)
watchOS 5.3.0 ('https://www.macrumors.com/2019/07/22/apple-watchos-5-3-ecg-canada/'): ECG app v1.18 (available in Canada and Singapore)
Score: 2 Votes (Like | Disagree)
GregJohn Avatar
76 months ago
Now just have to wait for them to add ecg in Watch OS 6 beta :P
Score: 2 Votes (Like | Disagree)
Eventer_ Avatar
76 months ago
Not showing up on iPhone running iOS 13 beta. Not sure if the beta is the reason, or it's just not showing up yet.
Same here

/edit

now found it
Score: 2 Votes (Like | Disagree)
Fynd Avatar
76 months ago
Same here
Likewise until I just spam refreshed it like the maniac I am and it showed up, so keep trying.
Score: 1 Votes (Like | Disagree)