Fitbit has evolved its line of fitness trackers from simple motion-activated step trackers to devices that are a lot more complete. The Fitbit Charge has emerged as the middle ground in these trackers, in the form of a wearable band, but with functions getting closer to sports watches.
The Fitbit Charge 4 makes the big step of adding GPS for on-the-go tracking of exercise; that's the missing piece of the puzzle that really prevented the Charge being the complete standalone solution. But it also moves the Charge into a new market position, where it's against new rivals and facing new challenges.
So how does the fourth-generation version of this popular Fitbit model hold up?
Is the Charge 4 a new design?
- Two strap sizes in box
- 1.57-inch touchscreen display
- Black or rosewood colours
- Water resistant (to 50m)
The Fitbit Charge 4 has the same overall design as the Fitbit Charge 3. That means there's a central tracker unit, with the heart rate sensors on the back, while the front occupies the display. There's a capacitive button joining the touchscreen operation, which is pretty simple to get to grips with.
There are two strap sizes (small and large) included in the box. It's incredibly easy to change these - you just have to press the button to release the strap and off it comes. The straps can be changed to suit your preference, with a range of accessory straps available in varying colours and finishes.
The advantage of a fitness band design is that it's a lot less bulky than a traditional watch. For many that's the appeal - it's slimmer, lighter, easier to sleep in, and less intrusive. Some, naturally will prefer the larger display of a regular watch, but there's still a huge amount of interest in this more compact design - and rightly so.
The downside is that the Charge 4 hasn't evolved beyond the Charge 3 in terms of its design, meaning it still uses a monochrome display. While the new information that this device will display is welcome, that information is rather small in scale compared to smartwatches with similar features, so it's not quite as glanceable as it is on, for example, the Garmin Forerunner 45. Glance at the Charge 4 outdoors on a run and you'll struggle to see all the information.
The Fitbit Charge 4 is water resistant to 50m, meaning it's safe to get wet - be that through sweat, swimming or just in the shower. It's safe to wash and Fitbit recommends that you rinse it off occasionally to keep the band clean.
Does the Charge 4 add GPS?
- GPS (global position satellite) for tracking
- 3-axis motion sensor
- Heart rate sensor
- NFC (Fitbit Pay)
The Fitbit Charge 4 packs in everything that was previously available on Charge 3 Special Edition devices, meaning that you get Fitbit Pay on this this device thanks to the integrated NFC chip. The only downside is that Fitbit Pay isn't as widely supported by banks as Google or Apple Pay, so you might want to open an account specifically to use with your Fitbit device. That's no hardship though, if you have a real desire to use it, it's just unlikely to work with your high street bank if you live in the UK.
The Charge 4 has a full range of motion trackers, allowing it track those traditional steps, as well as automatically detecting when you're exercising and log that via the app. This automatic detection works after a fashion, but won't tell you on the device what it's doing, so we suspect it's only figured out once it syncs to the app. We've seen things like "walk" accurately depicted, but if you want to track a run or yoga session, you're better off starting that as a manual activity, so you can look at your device during the activity to get the feedback as you go.
The motion sensors work with the heart rate sensor for sleep tracking, so the Charge 4 will give you a breakdown of your sleep stages to analyse how much rest you got - and give you a Sleep Score to help you easily keep track of that. This is broken down into segments and we like how it's shown in the app, although it doesn't balance this out with the rest of your daily activity as you'll get from Garmin's "body battery" feature - which tells you how much sleep you need to recover from strenuous days.
The biggest function of the heart rate sensor is in keeping abreast of your activity. It's used to assess your resting heart rate as a baseline and then to track your heart rate through exercises, either those it automatically senses or that your manually track, with support for major activities like running, biking and swimming - extending to pilates, yoga, weights and others that you can add as shortcuts to your device via the app.
Heart rate zones are reported, giving you feedback on the intensity and progress of your exercise, as you'd get from any other sports watch. Building on these functions is one of the new additions to Fitbit, called Active Zone Minutes.
Active Zone Minutes takes your age and your resting heart rate, then uses your active heart rate to assess your activity and award you points for it. The idea is to evolve beyond steps as a measure of activity - because while 10,000 steps might be a great target for a sedentary person, for any normally active person it is an easy target to hit and might not actually have any real fitness gains.
Instead, Active Zone Minutes (AZM) will look to reward you for higher heart rates. This is where running up the escalator, vacuum cleaning the whole house, going for a run, or doing a HIIT workout at home all counts - and where steps would make no sense at all. The aim is to hit 150 AZM a week (a World Health Organisation and UK NHS recommended level) and the Charge 4 will help you get there.
You can change the number of minutes you need, because it doesn't take much to hit that figure if you're a sporty person - but it's really a measure to support those who are less active, to show the benefit of, for example, 20 minutes of digging the garden. It all counts, and rightly so, the aim being to motivate you to be active in a range of different ways.
The addition of GPS to the Fitbit Charge 4 also supercharges your exercise. This, in addition to the altimeter, means you can accurately keep track of your exercise route, speed and elevation change. Above everything else, it's the addition of GPS that evolves the Charge 4 into a more accomplished sports device and makes the biggest difference over previous Charge devices.
How long does the Fitbit Charge 4 last?
- 7 day battery life
- GPS tracking for up to 5 hours
Above any other platform, Fitbit has an approachability: it's not too geeky, the information is nicely displayed in the Fitbit app, and there's plenty to explain what it all means and represents. That's great for those interested in fitness, without necessarily considering themselves to be athletes.
But the Fitbit Charge 4 can now give you much of the data that you'd get from a dedicated sports device now that it has added GPS.
That means you don't need to take your phone with you to get an accurate route trace, you can be more confident in the speeds reported and distance you've covered - and for anyone starting out with running, that's a great addition. It's accurate enough too: we tested it against the Garmin Fenix 6 - Garmin's top device - and found Fitbit to come out within about a few hundred metres distance variance. The route isn't always as accurate: Fitbit seems to smooth corners and the lines don't always match the path or road you've taken. For example, if you're running along a river bank, you might find your route is in the actual river, so absolute accuracy isn't as good as some.
The same applies to heart rate monitoring, where we found the Fitbit to give consistent readings, usually within 2-3bpm of our reference device. Again, it's close enough to be useful and give you a good understanding of what your heart is doing, but the important thing is that your device tracks you through different heart zones, gives you the data at the end, and reflects the real-world experience.
But there's a downside that comes with adding GPS: it's a big drain on the battery, moving the Fitbit Charge from a device that will last you a week, into one that only lasts a couple of days if you're doing regular GPS tracking. Of course, it all needs perspective. Ising it for a 30 minute run will eat about 10 per cent of the battery - on top of what you'd normally use in a day. We went cycling for 90 minutes and saw that battery drop some 40 per cent, which sort of shows you where the limits lie.
That won't matter to someone who is tracking their activity through the week with perhaps three or four 30 minute workouts, because it will still last the week. But if you want to regularly track longer activities, you're better off with something with a bigger battery. And that's the complex position that the Charge 4 finds itself in: in adding more features to improve this tracker, it's moved itself into a position where it's not as well placed to compete against rivals in terms of battery life.
Does the Fitbit Charge 4 play music?
- Smartphone notifications
- Customisation through the app
- Spotify control
Fitbit has supported a range of smartphone notifications for some time and those notifications continue on the Charge 4. You can control these functions from the app on your phone, which really does play a huge part in living with the Fitbit Charge 4.
The Charge 4 introduces Spotify control, but this doesn't extend to offering offline music support. What it will do - once you have linked your Spotify account - is allow you to control Spotify music on your devices. That's not just your smartphone, we've found that it will recognise other devices like Amazon Echo or Roku and let you play on those through Spotify Connect.
That's not immediately useful for runners, but it does mean you can control music easily during home workouts from your wrist. But there's a major usage problem: you can't access those controls once you've started a workout. That sort of reduces it to being a feature to control music when you're on your commute, and little else, again becoming a lifestyle rather than exercise feature.
While the Fitbit itself will give you some of your data, syncing with your phone really turns up the real results. It's via that app that the important data gathered by the Charge 4 is collated and packaged up. For example, on waking in the morning your Fitbit won't say too much, but sync with your phone and the app can tell you everything about how you slept.
Fortunately, the app is one of the best out there and although we use a wide range of devices and services, Fitbit is often the easiest to use and easiest to interpret. It's also compatible with a range of other services, so you can get all your data in one place. Fitbit doesn't go as far as platforms like Garmin Connect or Polar Flow with the detailed stats, but will still offer you access to things like training programmes.
The Fitbit Charge 4 is better geared for activity tracking than its predecessor thanks to GPS tracking, while the addition of Fitbit Pay means more independence for those on the move.
The compact nature and wide range of lifestyle tracking features makes it an attractive wrist-wearable proposition for anyone looking to increase their activity and monitor their progress, with the new Active Zone Minutes being a lot more useful than step counting.
It's too easy to compare the Charge 4 to any of the GPS-capable watches out there and find it come up a little short: a smaller display and shorter battery life does limit what the Charge 4 will do. But that's short-sighted and really needs to be balanced against the form-factor and what you want from a device.
So if you're looking for a fitness band that's a fully accomplished device, the Fitbit Charge 4 is hard to beat. Especially at this price - as a watch competitor would cost you a whole lot more.
This article was first published 13 April 2020 and has been updated to reflect its full review status
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