Apple Watch heart rate accuracy vs. rivals: devil is in the details

Apple wasn't kidding when it claimed that the Apple Watch Series 12 has the best heart rate accuracy of all wearables, but the extensive study also shows just how close some key rivals are under certain test conditions. Apple Watch Series 12 features improved health features - image credit: Apple. Other than the return of the popular ceramic casing, the Apple Watch Series 12's most significant update was in its improved health sensing system .