One feature is heart rate and sleep tracking accuracy.
The Quantified Scientist on Youtube has ever-updated charts in pretty much any of his videos that investigate the accuracy of a given health tracker wearable.
Check out the chapter titles with "Comparison w/ other watches" to see charts for heart rate accuracy and sleep accuracy across different product lines. Apple Watch is best in class (e.g. 99% convergence with Polar chest strap).
Yes, that seems to be consistent with the test results from DC Rainmaker. The Apple optical HR sensor is marginally better than Garmin in a few limited scenarios. So a win for Apple there and very technically impressive, although the difference would only tend to show up intermittently during certain intense activities. Serious athletes who really care about accurate heart rate will usually use a separate chest sensor as there are inherent limits to what an optical wrist sensor can do, especially if the wearer's skin is darker or tattooed or dirty.
Kind of grasping at straws to require 99.99% accuracy. At that point a Polar chest strap is better. Olympians use Garmin watches all the time and the heart tracking is pretty great in most of their more expensive watches.
Well, there's also sleep time accuracy and sleep stage accuracy. What about those?
And the whole point is that you don't need to wear a Polar chest strap and a bunch of sleep lab electrodes to get good results. We're talking about something you get to wear on your wrist that takes calls and does all sorts of things.
The Quantified Scientist on Youtube has ever-updated charts in pretty much any of his videos that investigate the accuracy of a given health tracker wearable.
You can find updated data in newer videos, but here's his video on the Apple Watch Series 9: https://www.youtube.com/watch?v=4igZ3DEhrk4
Check out the chapter titles with "Comparison w/ other watches" to see charts for heart rate accuracy and sleep accuracy across different product lines. Apple Watch is best in class (e.g. 99% convergence with Polar chest strap).