While some people on this board will swear by their Apple Watch data, my three year experience with it has been mediocre. A couple of years ago it picked up afib when I did a random EKG. I have elected the weekly report of afib options and it will indicate afib anywhere from 7% to 25% of the time. My Mayo cardiologist thinks it’s confusing PACs (multiple Holter Monitors have had my load at 10-12%) with afib and its algorithm does something funky with the data. Electing the Apple Watch option for identifying an irregular heartbeat in real time has never alerted to anything. I wear it to monitor my heart rate on my runs and get little use out of it otherwise.