Reluctantly I return this product, following an allergic reaction, erythema + eczema rashes on the skin in contact with the load HR. Allergic reaction occurred after about 3 weeks of use. Obviously this generation Fitbit tracker is also problematic. One can question the ability of the skin to tolerate contact with a non breathable synthetic material almost 24 hours on 24. In the end this may not be the matter that is the problem but the fact of having permanently in contact with the skin. About the device itself, I find very optimistic assessment of the number of steps between 20 and 30% of overvaluation most likely. A tooth brushing or any repetitive activity with the hand that carries the tracker will credit your account for tens or even hundreds of not fulfilled. No Gps to correlate the number of steps with a possible move. Number of floors climbed overvalued too. Some doubts also about the accuracy of cardiac monitoring, different values of my Polar chest strap. Unsealed product damage. Soft paying for the Premium version, a shame. Positive, battery life of 4 to 5 days. In short, tracker technology has yet to mature. We find no tracker that is both waterproof, accurate, reliable, with a good free app, a complete ecosystem, an interesting autonomy, an accurate cardiac monitoring, integrated GPS, a fair price and an engaging look. Just a matter of time ...
