The zones are personalised to you, based on your age, resting heart rate and max heart rate and the Charge vibrates to let you know when you’re moving between the zones. You start earning AZM when your heart rate hits the fat burn zone and you get double the credit for the minutes you spend working higher up the heart rate scale in the cardio and peak zones. It’s Fitbit’s attempt to use heart rate data to inspire us to move with more intent and intensity and ditch the blunt instrument of chasing step counts. By comparison, the likes of Garmin Connect and Polar Flow can feel a bit daunting, tailored to more ‘serious’ users.Īside from that new GPS, one of the biggest headline features is Active Zone Minutes (AZM). There’s a lot of detail but it never feels overwhelming. However, if you want to dig deeper into your data you’ll have to fire up the partner app, but there’s a pleasing simplicity to the just-enough overview of your day that the Charge offers.įor beginners, the Fitbit app is by far the best at keeping fitness and health simple. There’s just about enough screen real estate to present a decent selection of at-a-glance stats on the homescreen. In terms of the data displayed, you can choose from a small selection of watch faces and prioritise what’s most important for you. You get around 5 seconds before it goes back to black and there’s no option to override it. To add to the general frustration here, the Charge 4 also has a really aggressive auto hibernate, presumably to save battery life. It seriously hampers how useful the tracker is for running, cycling and walking and it not only affects things like looking at your real time pace and heart rate but it’s also hard to make the most of those Spotify controls.

The Fitbit Charge 3 has the same issue and it’s sadly not been fixed here.įor a fitness tracker whose central feature is about getting you off the couch to do more vigorous activity – likely outdoors – this is baffling.

It automatically adjusts to different light but we found it very hard to read on a lot of our test runs in brighter direct light. However, perhaps the biggest single problem with the Fitbit Charge 4 is how that screen readability suffers the moment you head outside and step into any kind of sunlight.

Charge 4 fitbit