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Apple Watch Series 4's ECG Feature Will Work Internationally When Set to U.S. Region

Apple revealed the Apple Watch Series 4 during an event in September, highlighting a new electrocardiogram (ECG) app that will be coming to users in the United States through a watchOS software update later in the year. Regulatory clearance is required for the ECG feature, and because of this it will be limited to the U.S. at launch, although the company is working on approval for other countries.

In a new post by 9to5Mac today, code found within iOS related to the ECG feature suggests that the ECG limitation is based on software, not hardware. This means that gaining access to the ECG app in a non-U.S. territory will be as simple as changing the region of the Apple Watch Series 4 and connected iPhone to the United States.

applewatchseries4ecgfeature
iPhone region can be changed by going to the Settings app > General > Language and Region, and then selecting the Region of your choice. Those who switch regions should note that the time, date, currency formats, and more will be affected by the change.

The ECG app on Apple Watch Series 4 works by placing a finger on the Digital Crown while wearing the watch. The electrodes in the Apple Watch detect the electrical impulses from your heartbeat and route the data to the S4, where it is converted into a signal for Apple's algorithms. This results in a heart rhythm classification that can vary between a normal rhythm to an atrial fibrillation. All of your ECG results are stored in the Health app in PDF format and can be easily shared with your doctor.

While the FDA has granted de novo clearance for the ECG feature, that's not the same as FDA approval and the agency does not recommend that the ECG feature be used by those under 22 or those who have already been diagnosed with atrial fibrillation. The FDA warns that Apple's ECG app is not designed to replace traditional methods of diagnosis or treatment and is intended for informational use only. The Series 4 is the first ECG product being offered over the counter directly to consumers.

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Top Rated Comments

tehStickMan Avatar
103 months ago
Sweet can't wait for it to tell me my heart PSI while Siri shows me that I'm 12 feet away from my next left-turn.
Score: 5 Votes (Like | Disagree)
103 months ago
FaceTime application is also software based and not hardware, yet it doesn't work for phones bought in countries where FaceTime is banned (even if US store or Location was selected).

The FaceTime App searches for the Model number from the approved list in Apple Servers or within the iOS itself and if it is not there it will simply not install nor show up in the APP store.

Therefore, i assume it will be the same thing for the ECG App, unless Apple makes an exception..
Score: 4 Votes (Like | Disagree)
103 months ago
Who in their right mind would ever think it was hardware based? Clearly Apple have not made two different watches - one type for US consumers and another for the rest of the world. :rolleyes:
Actually that's what I thought they did given that the cellular bands are different across different regions. The model numbers are certainly different between us/uk.
Score: 3 Votes (Like | Disagree)
103 months ago
Who in their right mind would ever think it was hardware based? Clearly Apple have not made two different watches - one type for US consumers and another for the rest of the world. :rolleyes:
Score: 3 Votes (Like | Disagree)
103 months ago
Should I be impressed with this? Either have it set to my country and have time/date/currency correct, or try to use the ECG (touted as one of the major features) and have basic functionality incorrect everywhere....
Actually changing the region seems to do much less than you would imagine; as far as I can recall it basically determines defaults for things like units, date display format etc - but crucially you csn still override these defaults to your preferred values.

When apple pay launched I tried setting my AW 0 region to usa and found I was able to use apple pay on it in London a couple of months before it launched in the uk. I was only able to link one of my wife's us credit cards since uk banks weren't supported, but other than that it worked great. As best I recall I was able to change pretty much all other settings to uk values so that the USA region didn't really bother me
Score: 2 Votes (Like | Disagree)
tromboneaholic Avatar
103 months ago
Has anyone actually tested switching region, doing an ECG and switching back to their original region? If that works, it would probably be a worthwhile update.
No one outside of Apple has been able to test it at all.
Score: 2 Votes (Like | Disagree)