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(Pocket-lint) - What does Fitbit have in common with the iPad? Simple: it has achieved that lofty position of becoming genericised (not sure what that means? Maybe you need to be heading back to school). 

Step into the playground and trademarks don't matter: all tablets are iPads, all smart speakers are Alexa, all fitness bands are Fitbit. And the Ace is a bona fide Fitbit designed for kids.

Do we really need a fitness tracker for kids?

  • Obesity rates are rising
  • 60 minutes activity a day is recommended

The cynic might say that this is Fitbit 'trying to catch them young'. You'll pardon the seditious turn of phrase, but you know what we mean. While marketing products to children can be controversial, Fitbit at least has a plan. 

Obesity rates in children are rising. In 2015/16 in the UK, one in three Year 6 children was recorded as overweight. That's children who are 11 years old.

Pocket-lintFitbit Ace image 5

Take your pick for the reasons for this: a diet of processed food from freezer to sofa; the rise of never-ending TV; the lure of phones, iPads (Apple or not), and games consoles; the decline of physical education in schools; parental fears of everything outside. Everything gets the blame, fairly or not. 

The government's recommendation is that children get at least 60 minutes of physical activity a day. And who likes to motivate people to be more active? Now we're back on script for the Fitbit Ace.

Fitbit Ace is basically a mini Fitbit Alta 

  • Two colours: purple or blue
  • Looks like a mini Fitbit Alta

You can see what Fitbit's plan is: to encourage children to hit that 60 minute target and make sure they are active, rather than settling into a sedentary lifestyle in those early years. Whether a fitness tracker alone can do this is a different matter, but kids want fitness trackers, because they see their parents and their peers with them.

There's now a proliferation of fitness trackers appearing in schools and a device like the Fitbit Ace has the advantage of also showing the time, thus killing two birds with one stone. From our experience there seems to be no stigma attached to wearing a fitness tracker: conversely, it seems to be the active children who are wearing them.

The Fitbit Ace is essentially a mini Fitbit Alta, the company's fitness band that's a little more stylish than the entry-level Flex. That sees a rubber strap meeting the central stainless steel unit with a small display on the top and a charging point on the rear. 

fitbit ace

It operates through touch on the OLED display, there are no buttons or controls to worry about, as it's designed to be as simple as possible. 

It's water-resistant too, so will survive the inevitable soaking in the rain or when (reluctantly) kids wash their hands. But it isn't designed for swimming, so if those 60 minutes of activity are spent busting out laps at the local pool, then the Ace isn't for you.

The battery life is stated at five days and we've found this to hold true. Because this is a tracker, there's little variation because you're not asking it to record an activity – there's no heart-rate sensor or GPS location tracking – so it doesn't suffer variable endurance times like some of the more fully-featured adult devices. So yes, a full school week is about right, after which it's a quick charge in a few hours to get it back to tracking.

The Fitbit Ace comes in two colours, either blue or purple. Both are bright and we like the approach that Fitbit is taking. Rather than designing something that's 'childish', it's designed to be like the other Fitbit products that kids will have seen adults wearing. While the Ace might not have the immediate appeal of the rival Garmin Vivofit Jr 2 with its character designs, there's less chance of the owner going off it because they no longer like that character.

Importantly the Fitbit Ace comes in a small size, so it's more likely to fit a child's wrist, aiming for ages 8+ years. The downside of such a design is that it's not hugely child-proof: within the first 24 hours on the wrist of an 8-year-old, our review sample had already attracted scratches. In some ways this adds character and hasn't affected the functionality in any way.

For younger users the fastening buckle might also be a little fiddly to use, but the release catch to remove the strap from the body is easily accessible: our 8-year-old never undoes the buckle, he simply releases the strap at one end and slides it off. Solutions, not problems – children easily overcome this minor design oversight.

Fitbit Ace features and functions

  • Sleep tracking
  • Step tracking
  • Activity tracking

The functions of the Fitbit Ace reflect those of Fitbit's other fitness trackers. The core hardware is an accelerometer, which detects motion. It's this that can track steps and activity, but there's no heart-rate sensor. The accelerometer also detects sleep, by recognising movement associated with different sleep phases.

fitbit ace

Sleep is hugely important in a child's development, being well rested is essential for school, as well as being important for general health (as it is for all people). The sleep tracking on the Ace will give you a better idea of how long you (or your child) has been asleep, bearing in mind that 10 hours is recommended for the ages to which the Ace is aimed, according to the Millpond Sleep Clinic.

We put a Fitbit Ace on the wrist of both an 8-year-old boy and 11-year-old girl, both of whom have been happy to wear it during sleep. But sleep tracking can be a little hit and miss, sometimes detecting being still as being asleep, so throwing in some usual results, like epic 16 hour sleeps following a quiet evening on the sofa.

You can set a sleep reminder, giving an alert on the Ace, while a paired phone will also let them know it's time to wind down and get ready for bed. It's a nice thought, but in reality we can't see any child wilfully doing as the Ace says – that's really going to be something that parents need to enforce with a good bedtime routine.

Pocket-lintFitbit Ace image 13

Still, we have found that waking times are pretty accurate – and the data is interesting to help illustrate sleep patterns and establish a sound understand of why sleep is important.

On the activity front, setting goals is a key part in motivating kids. The Ace offers rewards and badges for hitting goals. Within the first few hours of putting these fitness trackers on the wrists of our willing (ecstatic, even) test subjects, a competition had already started. Sibling rivalry is a powerful thing and some 20,000 step days ensued. 

The step tracking seems to be fairly accurate, but when comparing to an adult device, it's important to remember that your child is likely to be taking shorter steps, so might rack-up 12,000 steps when you only manage 10,000. In reality, the number doesn't matter – it only matters if there are no steps and you're totally sedentary.

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Pocket-lintFitbit Ace image 14

Activity minutes is a key metric – thinking back to those 60 minutes of activity per day that's recommended – and this is something that the Fitbit Ace measures and presents. It's basically a collection of movement episodes: the walking to school, running around the playground, after-school football, and so forth.

There's also the ability to manually log activities. You can enter the associated smartphone app and select an activity, its duration and length of time. However, as this is manual, it's likely that any child who doesn't have their own phone will forget to do this – although filling in those details could be a target and something that families do together. 

For older children with a phone, it's easy for them to dive into the app and log these details, especially when aiming to have five exercise sessions a week, for example. That said, we found that it was forgotten after a couple of weeks – once you can see you're active enough, the motivation to manually catalogue all your exercise runs out. Certainly, auto-recognition here would help.

Pocket-lintFitbit Ace image 11

What the Fitbit Ace doesn't give you is any data beyond steps and active minutes. The adult app on an adult account will give you calories burned, but the Ace equivalent does not. That makes perfect sense – 'calories' isn't really a healthy measure or meaningful in any way (there's no composition breakdown, for example), when the aim is increasing activity.

Display and information given

  • Time, steps, activity minutes
  • Call notifications from phone

The display on the Fitbit Ace is small and basic, only responding to touch. Our test children had no trouble using it, though, which is the main takeaway point. Most of the time the display will show the time, but tapping or swiping is all that's needed to progress through the data. The display abbreviates the thousands of steps to "k" and this initially caused some confusion: "I've walked 10k!". "No, you've walked 10,000 steps".

Aside from time it's only steps and active minutes that are shown – steps are easy to quantify, but in reality it's the active minutes you want to hit. This is the metric you want to be pushing, this is the goal you should be looking to achieve.

It's a family affair

  • Parent and child app views
  • Challenge setting

Children learn a lot from their family environment, so it makes perfect sense that the Ace will help you become a Fitbit family. Buying a Fitbit to encourage a child to be more active isn't going to motivate them if you're still sitting on your behind eating pizza and playing Xbox. It's very much a family affair.

Pocket-lintFitbit Ace image 10

Parents can keep track of how active kids have been through 'friends' views (ranked alongside other friends in your own app), as well as being able to switch their app to a particular child's view. Indeed, when you setup a Fitbit Ace with a child user, it's still the parent's account so you don't face age restrictions or need a non-existent child's email address or anything else. This is all good, because there's no creation of accounts beyond your reach. 

You can create a family account, but only link one Fitbit device to each account. When switching into the child's view within the Fitbit app it then prompts the phone to sync with that child's device. In reality, if all your Fitbit devices are syncing to the one phone, you'll be forever switching users in the app to make the syncing happen – it doesn't all sync in the background – which is a potential problem. Ultimately, everything works a lot better when your children have their own device.

In their own words...

But who really cares what an adult thinks about the new Fitbit for kids? We decided that to cut through the waffle and bring you an unfiltered verdict.

Pocket-lintFitbit Ace image 7

Lottie, aged 11 years

"One of the best things about my Fitbit is all the Challenges you can do. You can challenge friends and family to see how far you can walk or who walks farthest fastest. I like challenging my brother.

"It always encourages me to be more active and I like how comfortable it is to wear. I like how easy it is to change the straps."

Pocket-lintFitbit Ace image 8

Leo, aged 8 years

"I like my Fitbit because there are lots of abilities like telling the time and date, steps and active minutes on the screen. When you sync it to a phone you can make friends and challenge them. You can make it track your exercise, track hourly activity and even track your sleep!

"Another good thing about it is you can take the strap off and put another strap on."


It's a good thing that Fitbit offers a tracker for children and has considered how younger users fit into the Fitbit world. As a parent, knowing that you create and control that account is the best part of the equation, because you're not setting up another system of data logging that's outside of your control.

While the feature set of the Fitbit Ace is pared down compared to a fully-featured adult device, the omissions aren't too consequential. It performs well, and it's only really automatic exercise detection and slicker family account sync to multiple devices that we'd like to see.

We can't help feeling the price is a little high, though, but as an introduction to the Fitbit world for kids, the Ace is a great starting point. 

Also consider

Garminalternative image 1

Garmin Vivofit Jr 2

A real rival to the Fitbit Ace, the Garmin is designed with greater appeal for younger kids with its character designs – you'll see Captain America above, for example – but there's also the risk that as tastes change those characters will fall out of favour. Garmin rolls in chores, with parents controlling the experience, while also getting steps, activity and sleep data.

Writing by Chris Hall. Originally published on 13 March 2018.