Technical help needed about buying a smart watch

[Mischance]

I am probably one of the older mumsnetters and am hoping that more technically savvy young members might be able to advise me here please.

I need to get a smart watch with an ECG function that either works as a stand-alone or is compatible with an android phone. So I guess that eliminates an Apple Watch. But would Fitbit perhaps be OK?

I need ECG rather than just heart rate.

I have tried to get an answer on this from the companies but so far with no success.

If anyone could point me in the right direction I would be very grateful. Lots of thanks.

I've never heard of one with an inbuilt ECG, that is a specialist medical function, I thought. I only know of ones with heart rate monitors. I have the Garmon forerunner and really like it, easy to use and plenty of general health stats including average heart rate.