Apple Watch Ultra 2 beats Garmin, Whoop, Samsung and other smartwatch brands in sensor comparison

Rob ter Horst, a scientist specializing in bioinformatics and the host of the YouTube channel The Quantified Scientist, has tested the sensors of the Apple Watch Ultra 2 (from $799 on Amazon) while running the latest watchOS 26 beta version. He compared it with numerous other smartwatches in order to determine whether users can rely on the data collected by Apple's flagship smartwatch.

First, the heart rate sensor was tested. During an indoor running workout, it collected data that was nearly identical to the reference device, a Polar H10 chest strap in this case. While there were minor deviations, they are small and therefore rather insignificant in practice. This puts the Apple Watch Ultra 2 on par with the best competing smartwatches, such as the Huawei Watch 5. For comparison, the Whoop MG showed a deviation of about 6% from the reference device, while the Garmin Forerunner 570 deviated by about 7%. Meanwhile, the Garmin Fenix 7 was off by 9%, and the Samsung Galaxy Watch 7 by only 3%.

During outdoor runs and cycling, the Apple Watch Ultra 2's heart rate sensor also delivered almost the same data as the reference device, so the gap to the competition grew even bigger. The Garmin Forerunner 570's cycling data deviated by 12%, while the Whoop MG's deviation increased to over 15%. With all that being said, a dedicated heart rate chest strap is still a worthy investment for weightlifters. Like many other smartwatches, the Apple Watch Ultra 2 cannot detect a heart rate when there is too much tension on the wrist.