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How to buy the best activity tracker or fitness watch

How to buy the best fitness watch

By Hannah Walsh

Article 2 of 3

A fitness watch, activity tracker or smartwatch? Do you need GPS? Our expert guide will help you pick the best wearable for you.

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The best fitness or GPS watch will provide you with accurate, comprehensive and easy-to-understand data about your exercise or performance in a particular sport, which you can then use to monitor and improve your progress. 

Whether you’re interested in tracking your running, cycling or swimming, measuring heart rate or just keeping an eye on daily activity, there’s a wearable out there for you.

This also means there are plenty of different devices to choose from, and that’s where we can help. Is a fitness watch, fitness tracker or smartwatch right for you? What features will you need? And how much should you spend?

Once you have the answers you’re looking for, find the right model for you by taking a look at our expert fitness watch and GPS watch reviews.

How much will a good fitness watch or GPS watch cost?

Fitness or GPS watches are priced from around £60 up to more than £500. If you just want a simple way to track your distance and speed on a run, a budget model could be worth a look. They lack the features of pricier models, and tend to have a basic greyscale screen, but that doesn't mean they won't provide accurate data. 

Our cheapest Best Buy fitness watch is less than £120

Those looking for devices aimed at specific sports, such as cycling or golf, or wanting advanced sensors or feedback – such as heart rate, VO2 max (the maximum rate of oxygen consumption), fitness plans or good motivational tools – will need to spend more.

Buying the best fitness watch or GPS watch

One of the most important things to consider when buying a wearable is what exactly you want to use it for. This can range from simple step tracking, to notifications such as calls, texts or emails, right through to in-depth analysis of your fitness or a particular sport.

There are a variety of wearable options available, and we can ensure you pick the right device for you.

Fitness watch vs activity tracker vs smartwatch

Fitness or GPS watch?

A fitness or GPS watch is a wrist-worn device that offers advanced tracking of particular types of exercise or sports. Many focus on a specific sport, such as running, cycling, swimming or golf. Others offer multi-sport tracking – so you can track your whole workout from the treadmill to the pool.

There are some activity trackers that have built-in GPS, but it's still not in every device. The majority of fitness watches are able to operate independently to your phone, thanks to built-in GPS. This means you can leave your phone at home while out for a run or cycle.  

  • Pros: More in-depth or focused tracking makes these great for fitness fanatics or those wanting to focus on particular types of exercise.
  • Cons: Fitness watches tend to be pricier than fitness trackers. They will also be bulkier, so consider how often or how long you want to wear your device.

Activity tracker

An activity or fitness tracker is a band or clip-on device that can give you an insight in to your day-to-day activity, such as step or distance tracking, calorie counting or sleep. Some offer more advanced sensors for tracking, such as heart rate monitors, and some basic smart notifications such as text or email.

The best trackers are accurate, comfortable and a breeze to use. The worst over or understate your data, and can be a pain to wear and use. If you think a fitness tracker is the best option for you, find out which models impressed in our tests - take a look at our Best Buy fitness watch and activity trackers.

  • Pros: We’ve found some great fitness trackers at low prices. So if you’re just interested in finding out more about your daily activity to help you get fitter, you won’t have to break the bank. There are plenty of models designed with comfort in mind too, so you will be able to comfortably wear a tracker day to day.
  • Cons: While some models offer the option to track different types of sports or fitness activities, most trackers are fairly limited in the choice of exercise tracking and stick to steps, distance and calorie tracking.


The best smartwatches link together notifications from your smartphone, such as text, calls, emails and social media messages, with comfort and style. The best let you easily view and respond to notifications, and some offer some basic fitness tracking. We’ve also found devices with limited features, difficult-to-read screens and uncomfortable straps.  

Want to avoid the poor performers, but like the sound of being able to keep in touch from your wrist? Take a look at our smartwatch reviews.

  • Pros: Great for keeping up to date with and replying to notifications. The best also offer some accurate fitness tracking – such as steps, calories and sleep – and even heart-rate monitors.
  • Cons: Like fitness or GPS watches, smartwatches tend to be on the pricey side. They won’t be able to track different sorts of exercise or sports, and a lot of smartwatches have a short battery life - so will need recharging regularly.

What features do I need?

Accelerometer – An accelerometer will measure your speed, and helps to smooth out any GPS blips when calculating distance. If you do any running on a treadmill you’ll need a fitness or GPS watch with an accelerometer to track your run.

GPS – If you want to track how far you’ve run or your route - without your smartphone glued to your side - built-in GPS is a must-have. Some fitness watches are able to use the GPS on your smartphone, but this isn’t ideal if you want to leave your phone at home when you run or exercise. If you want to find a device with GPS built-in, check out our pick of the top five fitness watches and activity trackers with built-in GPS.

Heart rate monitor – Measuring heart rate can be useful for a variety of reasons, from knowing when you’ve reached the active heart rate zone to measuring improvements in training. It can also be used to measure VO2 max (the maximum rate of oxygen consumption), which can be useful for climbers, people preparing for a particular event and athletes. We've rounded up the best devices for keeping track of your heart-rate, including trackers and watches, in our top five fitness watches and activity trackers with heart-rate monitors.

Water resistance  – Typically, if your fitness watch is rated for water resistance, there will be a list of obscure letters and numbers to reference how well protected it is against water. For example, an IP68 rating means that the device can be immersed in water at a depth of a metre or more, for a set period of time. An ATM rating is also important; a 1 ATM rating or higher means the device is water resistant up to 10 metres of pressure or higher. The pressure is important because, while you can take the fitness watch down to a certain water depth, if you sprayed the watch with a high pressure hose, it may not survive the experience. To find out which devices made a splash in our tests, see our pick of the top five best fitness trackers for swimming.

Smart notifications – Not all fitness or GPS watches have smart notification capabilities, which could work in your favour if you don’t want to be bothered by emails during your workout. If you’re hoping for a device to help you train and stay connected, then look for one that can be linked with your smartphone for notifications.

Third-party apps – If you already use an app on your smartphone or wearable, such as Strava or running app Map My Run, you won’t want to lose access to your data or the in-depth analysis dedicated apps can offer. Look for a fitness or GPS watch that will let you pair with app services and sync the data from your wearable.

Music – If you want to listen to music on your run without taking multiple devices out with you, there are a few fitness watches (such as the TomTom Spark) that have storage built-in for music as well as headphone jacks or Bluetooth. It’s not a common feature at the moment, though.