New research suggests that the Apple Watch accurately tracks heart rate (4.43% error) and step counts (8.17% error), but is less reliable for calories burned, with a 28% inaccuracy rate. Despite the limitations, the researchers emphasized the watch's value for tracking habits and staying motivated. "Think of it as a helpful guide, not a diagnostic tool,” the head of the study commented. Another noted how Apple is refining the technology over time to make it more accurate ...