This is according to a recent study conducted by Stanford University in which they found that the Apple Watch’s heart rate tracker is the most accurate out of the various fitness trackers that they have tested. This includes wearables such as the Samsung Gear S2, the MIO Alpha 2, Microsoft Band, Fitbit Surge, and so on.
Based on their findings, the Apple Watch managed to come out on top of the competition with a median error rate of 2%, with the Samsung Gear S2 being the least accurate of the bunch with a median error rate of 6.8%. However the Apple Watch is far from perfect because the researchers also found that in terms of calorie tracking, the Apple Watch might not be so hot.
It had an error rate of nearly 40% which sounds rather bad. This is versus the Fitbit Surge that came out on top with 27%, so maybe don’t use the Apple Watch if you’re trying to track your calories.