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Top activity trackers and fitness watches for 2019

By Christina Woodger

Fitness trackers can specialise in a variety of activities - from outdoor pursuits to swimming, but choose one that's right for your needs to get the best results.

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Whether you’re looking for a simple activity tracker for monitoring steps, calories and distance travelled, or you want one with more advanced features for running or swimming - fitness and activity trackers can cover the lot.

In this guide we pick out some of the best wearables for a variety of activities, based on how they've fared in our tough test labs. 

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Best overall fitness trackers 

The trackers below are great all-rounders. They should be able to handle a wide range of sports and activities, and tracked steps and distance with little error, as well as being comfortable and durable. 

Best fitness trackers


Our top-scoring fitness tracker comes with built-in GPS and heart-rate monitoring. It tracks fitness data accurately in our tests, and it’s waterproof for swimming, too.


This tracker has an impressive range of fitness and smart features, including built-in GPS and sports-specific tracking. It's easy to use and has a bright, clear screen. You'll need to charge it frequently, though.


This tracker is ideal for sporty types who are looking for a slim, unobtrusive tracker, but don't need sophisticated smart features. It's cheap considering its high quality of its build and GPS features.

Best fitness trackers for accurate step counting 

Every fitness watch or activity tracker will capture your steps. It's a useful metric for those wanting to keep an eye on their daily activity levels. But not all of them are equal when it comes to the accuracy of their tracking or the motivational tools they use to get you moving more.

We’ve found several fitness watches and activity trackers that overstated or understated steps taken by more than 30% during everyday tasks, clocking up steps when our test participants were simply flipping the pages of a magazine. But it’s not all bad news, as we’ve also found lots of trackers that are strides ahead when it comes to accuracy – including the devices below.

Best fitness watches and activity trackers for step tracking


This watch tracks step count brilliantly. And it goes beyond that – it’s an expensive, feature-packed watch that offers in-depth running analysis and activity tracking. It's also waterproof for use in the pool, it has a long battery life and will let you receive smart notifications.


A versatile fitness watch with an integrated heart-rate monitor, altimeter and barometer. It's also waterproof for use in the pool. It's expensive, so not one for casual runners.


This watch tracks step count very accurately. It’s more than a humble step-tracker, though. It offers advanced running data, GPS tracking, VO2 max estimates and heart-rate monitoring.


This device tracks step count very accurately. It also has built-in GPS and a heart-rate monitor, and it's simple to use.

How we test for accurate step tracking

A pedometer is the most basic sensor, and it's one you’ll find in every fitness watch or activity tracker for counting your steps. 

To check the accuracy of step tracking, our test participants walk on a calibrated treadmill at 4.8km/hour for 10min and run at 9-10km/hour for 10min. They go through a series of daily tasks, including carrying shopping while walking up steps, sweeping the floor, loading and unloading the dishwasher, and reading a magazine. 

We’ve tested step tracking devices that range in price from less than £20 right up to nearly £500. But, price has no correlation with the accuracy of tracking. In fact, we’ve found a £20 tracker that counted steps completely accurately, while some pricier devices struggled. 

For more on accuracy, check out our guide to the most accurate fitness trackers.

Best fitness trackers with heart-rate monitors 

A built-in heart-rate monitor is a useful feature and, if accurate, can help you track your active heart-rate zone (particularly useful if you’re looking to burn fat), and measure improvements in training. We’ve tested fitness watches and activity trackers with heart-rate monitors from brands including Fitbit, Garmin, Polar and Samsung, among others, but some devices have been beaten by our tough tests. In fact one device understated heart rate by nearly 60%.

Best fitness watches and acitivity trackers with heart-rate monitors


This device tracks heart rate very accurately. It can track a range of sports, it has an altimeter and barometer, and it’s waterproof for use in the pool. It's expensive, so not one for casual exercise.


A great, if expensive, watch, with great heart-rate monitoring. It also offers advanced running data, GPS tracking and VO2 max estimates.


This watch is very accurate when it comes to heart-rate tracking. It’s ideal for casual runners as it has built-in GPS and it's simple to use.

How do we test heart-rate tracking accuracy? 

Our test participants go through a series of tasks while wearing a ‘telemetry monitor’ chest strap, which measures the electrical signals from their heart. They walk on a calibrated treadmill at 4.8km/hour for 10min and run at 9-10km/hour for 10 min and go through a routine of daily tasks, including loading and unloading a dishwasher, carrying the shopping and sitting reading a magazine. 

We compare the heart-rate readings from the telemetry monitor with the fitness watch or activity tracker, which allows us to calculate how accurate the device is. We know consistency is just as important as accuracy, particularly when using changes in heart rate to monitor improvements in fitness over time. So we repeat our walking test to see if the trackers consistently overstate, understate or hit the accuracy mark.

Best GPS-enabled fitness trackers for running 

If you want to leave your smartphone at home while still tracking your distance and route using your wearable device, built-in GPS is the extra feature to look for. Wearables with built-in GPS used to be at the pricier end of the spectrum, but we’ve tested several devices with this feature for under £100 – including one of the models in the table below.

Best fitness watches and activity trackers with built-in GPS


This watch tracks GPS brilliantly. It also offers in-depth running analysis and activity tracking, a long battery life and smart notifications. It’s waterproof for use in the pool, too.


This device scored brilliantly in our GPS test. It has plenty of other good fitness features too, it tracks steps and distance accurately, it can be worn while swimming, and its battery life is good.


This watch tracks GPS brilliantly. It has plenty of other good features, too – it’s a versatile fitness watch with an integrated heart-rate monitor, altimeter and barometer and it’s waterproof for use in the pool. It's expensive, so not one for casual runners.

How we test for GPS accuracy on fitness trackers and watches

All fitness watches and activity trackers with built-in GPS are tested for accuracy on a 1km route. The route includes dense trees and an underpass to add the challenge of potential loss of GPS signal. We even add a hill climb and compare the elevation data to Ordnance Survey topographical data to get an idea of the accuracy of the distance calculator. 

Fitness watches with advanced running capabilities are put to the test on a longer, 5km, run too.

Best waterproof fitness trackers for swimming 

Not all fitness watches or trackers can be used in the water. And those advertised as being pool-friendly don’t always give you much data. 

But others can give you a more comprehensive picture of your swimming, tracking information such as number of lengths, pace, stroke rate, distance, duration and calories burned. Some can give you a SWOLF rating (a measure of your swimming efficiency) and some can automatically detect whether you're doing front crawl, breast stroke, butterfly or another common stroke. One we tried out even detected we were at the leisure centre based on GPS and asked if we wanted to begin a pool swim. 

Be aware that, if you want to use a float at any point, to force yourself to use your legs, your device probably won't log your lengths, as you're not moving your arms. Also be aware that many devices can't give you heart-rate data in swim-mode. However, some can be paired with a heart-rate monitor chest strap. 

Here are the most detailed wearables for swimming we've come across. 

Best activity trackers and fitness watches for swimming


You'll get time and distance on the watch itself while you swim, and detailed metrics, such as pace, calories, strokes, swimming efficiency and speed, in the app once you've finished your swim.


It's easy to use while you swim, and gives you data such as stroke rate and total strokes per length, both in open water and in swimming pools.


A watch aimed at hardcore athletes (no need to pay so much if that doesn't apply to you). It'll give you details of your stroke, pace, heart rate, calories and swimming efficiency.

Water ratings explained

Water ratings are a confusing topic, and rating codes may mean different things depending on the type of device they are referring to. In the tables below we look at the different ratings, and what each one means in terms of how you can use your fitness tracker around and in water.

There are two main ways to find out what level of water protection or resistance your fitness tracker has. The first thing to look for is the Ingress Protection (IP) rating. These are set by the International Electrotechnical Commission (IEC), and refer to the protection provided by the casing of an electrical device in fresh water. 

The first digit after the IP reflects the level of protection against solids, such as dust or grit. The second represents the protection against moisture. An IP code with an X in place of either number means the device hasn't been tested for that element. For example, a fitness tracker with a rating of IPX7 has been tested for moisture protection, but not dust.  

IP code Level of protection
0 No protection
1 - 3 Protection against light rain
4 - 6 Splashproof
7 Protected from immersion in water with a depth of up to 1 metre for up to 30 minutes
8 Protected from continuous immersion in water with a depth of more than 1 metre

The second is the water-pressure rating. These are standards set by the International Organisation for Standardisation (ISO). Pressure tests are measured in atmospheres (ATMs), and replicate the level of pressure at certain depths of water.

Water ratings Level of protection
1 ATM Resistant to pressure equivalent to a depth of 10 metres. Splashproof, but not shower or swim proof.
3 ATM Resistant to pressure equivalent to a depth of 30 metres. Splashproof and shower proof, and should be fine if accidentally submersed. Not designed for swimming.
5 ATM Resistant to pressure equivalent to a depth of 50 metres. Splashproof, shower proof, can be worn swimming and snorkelling in shallow water.
10 ATM Resistant to pressure equivalent to a depth of 100 metres. Splashproof, shower proof, swimming and snorkelling. Not designed for deep water diving or water sports.
20 ATM Resistant to pressure equivalent to a depth of 200 metres.  Splashproof, shower proof, swimming and snorkelling. Surface diving and watersports, but no deep-water diving.

Not found the perfect product for you? Browse all of our fitness watch and activity tracker reviews.

Fitness trackers to avoid 

There’s a great selection of wearables in the tables on this page, but our tests have also uncovered products that are inaccurate, uncomfortable to wear, and don't meet battery life claims. These devices will soon end up shoved in a drawer, so make sure you pick the best fitness tracker rather than one of the dodgy devices in the table below.

Activity trackers to avoid


Struggles to track step count and heart-rate accurately, the screen is very easily scratched and the app is unintuitive to use.


It's accurate, but it's not a pleasure to use – you're expected to trim the band to fit your wrist and the silver edging wears away in just a few days.


A case of style over substance, sadly. It really struggles with accuracy, overstating calorie burn during walking and running, and understating distance. The companion app is pretty basic, too.

How we test fitness trackers 

Our tough lab tests go the extra mile, with specialist lab equipment to check the accuracy of the tracking capabilities of each device, meaning you'll be able to precisely monitor your activity and fitness. Our panel of users gets to grips with the trackers over a number of weeks, so you can be sure we have the best advice when it comes to set-up, ease of use and comfort.

We walk and run on a treadmill, carry shopping and load and unload a dishwasher, all while wearing a heart-rate monitor or special mask for analysing breathing (which helps to track calories highly accurately).  

These are just some of the lengths we go to in order to check how accurate a fitness tracker is. Our users try out the trackers for several weeks, too, so they can rate them fairly on comfort and usability.

The best fitness trackers are accurate, comfortable and a breeze to use, but not all devices are built the same. Poor performers in our tests have failed to track any activity accurately, and we’ve found models that are so uncomfortable our users wouldn’t want them even as a gift. 

To find out more about our tough lab tests, head over to how we test fitness watches and activity trackers.


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