Undoubtedly the most exciting feature of the new Apple Watch Series 4 is the ECG functionality. However, it isn't available yet and we are still waiting for Apple to enable it via a future update. And according to inside sources, watchOS 5.1.2 is going to be the one to bring it.
The software version is currently in beta testing and isn't yet available for the public. But once it arrives, it will be able to read your heart rhythm. It can help detect atrial fibrillation or just an irregular heart rhythm.
Apple promised to enable the feature by the end of this year but it's still unclear if it will manage that.
On a side note, the obtained training document states that you need at least iPhone 5s for the device to work and iOS 12.1.1 installed.
Yet again, if you are outside the US, don't get your hopes up because it will take some time for Apple to enable the feature outside the country. After all, there's are a lot of licenses that Apple needs to obtain and the USA's FDA was just the first.
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