It’s useful stuff, sure, but only if you know what to do with it – and I’m betting most people that would buy one of these won’t.

You’ll have to dig around in the app to find them, but there are handy fat burn, cardio and peak heart rate bar charts that’ll give you a better idea of how to get the most out of your exercise. It takes your age, height, weight and resting heart rate, then compares it with other people in your age range to get a score. Fitbit calls this the Cardio Fitness Level, but works in the same way. The Charge 2 has a fitness-friendly party trick, in that it can calculate VO2 max. The readings were lower than a chest strap, too – but oddly the app showed a more accurate reading after I’d finished my session. The onscreen heart rate often lagged behind the actual interval, showing too low during each activity and too high during each rest. Things weren’t quite so rosy for high intensity interval training (HIIT), either. You’ll have to bring your phone along for the run if you want to keep an eye on your pace. There’s no built-in GPS, which is hardly a shocker at this price, but still annoying if you like to track your workouts. Step counts were accurate, even over long distances, and pulse measurements were on par with a more expensive running watch/chest strap combo.

It is more of a fitness tracker rather than being a normal watch.

the watch features several advanced technologies like optical heart rate sensors, a bigger OLED display, a connected GPS, and so on. After its launch, the entire market went crazy for it. It might take a bit longer to lock onto your heart rate than a chest strap, but the Charge 2 did a great job at tracking runs. Fitbit Charge 2 is the first model in the entire series.

Charge 2 fitbit