
25 February 2021
Which Apple Watch should you buy?
Confused by the number of Apple Watch versions available? We explain the differences and reveal which came out on top in our tests.

In this article
Apple is the leading name in the smartwatches market. An Apple Watch puts your phone’s screen on your wrist, giving you notifications and apps without you needing to draw your phone out of your pocket – plus fitness features and cutting-edge health features. If you go for an LTE version, you can leave your iPhone safely at home and still stay connected. All the watches share the same iconic design, but what are the differences between them?
Processor, price and features – these are just some of the differences between the Apple Watches. We take a look at the Apple Watch range, from the Series 1 through to the Series 6 and SE.
There's a lot to love about Apple Watches, but they're not perfect either: for example one watch was out by 50% when measuring steps in a routine walking- around- the- house- doing- chores scenario.
You can also see how Apple Watches compare to other smartwatches by heading to our list of the best smartwatches.
Or, if you just want the most accurate smartwatch, regardless of brand, check out our guide to the How accurate is your fitness tracker or smartwatch?, which reveals how each smartwatch and fitness tracker we've tested scores for step-tracking, distance-tracking and heart rate accuracy.
Logged-in Which? members can view the full Apple Watch results in the table below. If you’re not yet a member, join Which? to get instant access.
Table updated February 2021
Not found the product for you? Browse all of our smartwatch reviews.
How much will an Apple Watch cost?
Whichever watch you go for, you'll have a number of customisation options. So the price you pay will depend on factors like size of the screen, the material of the band and casing, whether you go for a designer version and whether you want LTE (also known as cellular connectivity).
The current range includes the Apple Watch Series 3 GPS, Series 3 GPS + Cellular, Series 6 GPS, Series 6 GPS + Cellular, SE and SE + Cellular.
Apple Watches range in price from £199 for a Series 3 with an aluminium case and a sports band, right up to more than £1,000 for a designer Hermès version of the Series 6.
The Apple Watch Series 6 with GPS starts at £379 for the smallest version. The Series 6 with LTE starts at £479 for the smallest version.
The original Apple Watch, the Apple Watch Sport, Series 1, Series 2, Series 4 and Series 5 aren’t available to buy from Apple anymore.
The Series 4 was discontinued when the Series 5 was launched, and the Series 5 was discontinued when the Series 6 and SE were launched this year. But a couple of retailers are still selling the Series 5 while stocks last, and you can pick up second hand versions of several of the older models from Apple's Refurbished store. Apple is still selling the Series 3.
Choosing the best Apple Watch
All of the models in the Apple Watch range are compatible with iOS devices, such as your iPhone and iPad, and offer similar features. Find out what sets them apart in our tough tests, or read on to see the different benefits each version of the Apple Watch has to offer.
- Apple Watch Series 3 GPS review
- Apple Watch Series 3 GPS + Cellular review
- Apple Watch Series 4 GPS review
- Apple Watch Series 5 GPS review
- Apple Watch Series 6 GPS review
- Apple Watch SE GPS review
watchOS
All Apple Watches run watchOS, Apple's operating system. This is designed to work exclusively with iOS devices and so can’t be used with Android or Windows. Check out our smartwatch reviews for devices that are compatible with other operating systems.
WatchOS is a touch-based interface that offers the gamut of smart features beyond reading and responding to messaged and emails, making and receiving phone calls, and dealing with social media notifications. You can also use the watch to craft social media posts, such as tweets, from scratch, and make contactless payments via Apple Pay. You can use the voice-command feature courtesy of Siri. You can take screen shots, unlock your Mac from your watch if you can't be bothered to type in the password yourself, and you can send your live location direct from your wrist.
You can share your activity rings with friends if you want to show them your progress, and you can comment on friends' activity rings.
For a bit of fun, you can hear the time spoken aloud by Mickey Mouse or Minnie Mouse.
In September 2020, Apple released a new version of its operating system – watchOS 7. This comes pre-installed on the Apple Watch 6 and Apple Watch SE and is available for the Series 5, 4 and 3.
Interesting new features of watchOS7 include:
- Sleep-tracking – previously you had to install a third-party app if you wanted to use your watch for sleep-tracking
- Family set-up – allowing you to pair multiple watches to the same iPhone, meaning you can buy Apple Watches for members of the family who don't have a smartphone (including children)
- Child-friendly features – including fitness-tracking for kids, parental approval for contacts and apps and the ability to set a Schooltime mode, so children aren't distracted by their watch during study hours
- Handwashing detection – particularly relevant in the current climate. If it senses that you're washing your hands, your Apple Watch will time you and encourage you to keep going if you've stopped before the recommended 20 seconds. It can also remind you to wash your hands when you've got home
- Innovations for watch faces – making them more customisable with your favourite colours and 'complications' (widgets). You can also now share watch faces with family and friends.
- New workouts – fitness tracking for dance, functional strength training, core training and post-workout cooldowns
- Cardio fitness levels – you could previously get this information during your workouts, but now you'll be able to get it when you're walking around too. It's based on your Vo2 max (a measure of your body's ability to consume oxygen during exercise)
Design
All Apple Watches look similar, with a rectangular face, touchscreen display and circular button on the side for scrolling through menus and notifications. As of the Series 4, the digital crown gives haptic feedback (small vibrations) for what Apple calls a more 'precise, mechanical feel'.
In 2020, Apple released two new watches: the Series 6 and the SE. The SE (pictured below) is being pitched as the cheap Apple Watch, although, with a starting point of £269, it's clearly not for those on a budget.
For the Series 6, you can choose from a wider range of case colours, including red and blue. In terms of material, you can choose between aluminium, stainless steel and titanium. The SE comes in aluminium only, and in three colours: gold, silver and grey. The Series 3 comes in aluminium only, and in two colours: silver or space grey. It was available in ceramic for a time, so you might see second-hand versions with ceramic cases, but these have been discontinued.
Whichever watch you go for, there's a wide range of straps to choose from. Apple has come a long way from the Series 1, which could only be bought with a rubber strap. For the Series 6 and SE you can buy silicone straps, nylon straps, leather straps and designer straps. If you already own a band from a previous Apple Watch, you'll be able to reuse it for the Series 6 or the SE.
Processor
All Apple Watches use an on-board processor, which was updated for the Series 6 and is designed to be faster than the Series 5.
The original Apple Watch has an S1 chip, Series 1 models have an updated S1P dual-core processor and Series 3 has an S3 processor, which is more powerful and includes on-chip GPS functionality. The Series 4 has a new dual core 64-bit processor for (Apple claims) double the performance. This was updated for the Series 5 – and now again for the Series 6, whereas the SE still has the S5 chip dual-core processor.
Built-in GPS
Built-in GPS lets you track your routes without relying on your smartphone, so you can leave your mobile at home when heading out for a run. It’s available on the Series 3, Series 4 and Series 5 models.
Water-resistance
The, now discontinued, Series 2 was the first range of smartwatches from Apple to be made water-resistant, with a rating of 5ATM (so water resistant to up to 50 metres in depth for 10 minutes). All subsequent Apple watches have followed suit. This means they're fine to wear while showering or swimming, even in open water, but won’t be suitable for watersports or diving.
Check your strap is swimproof if you plan to take your Apple watch swimming, though.
It’s currently impossible to seal a speaker, because it needs air to produce sound, but Apple has got round this by creating a speaker that lets water in and then uses sound vibrations to eject it back out. We checked the waterproofing claims for the Series 3 in our labs – find out if it passed, and if it’s a good option for keen swimmers, by diving into our full review.
What's new with the Apple Watch Series 6 and Apple Watch SE?
The Series 4 was a much bigger step forwards in many ways than the Series 5, Series 6 or SE. That's presumably why Apple is continuing to sell the Series 3, but has discontinued those in between the 3 and 6: it knows most people will want something more recent.
Exciting features which you'll find on the Series 4, 5 and 6 include three FDA-approved heart monitors. These watches can:
- notify you if your heart rate is too high or low (the Series 3 notified you if it was too high but not low)
- detect atrial fibrillation – irregular heart rhythms. Apple is being careful not to say that it definitely will detect this, mind you - but it could do
- take ECG (electrocardiogram) readings which you can share with your doctor.
They can also detect if you've fallen over and call 999 on your behalf if you've been immobile for a minute. The cellular versions will do this even if you're not near your phone.
The SE can detect falls, but it can't take ECGs. And it can't take blood oxygen (SpO2 or pulse oximetry) readings, which the Series 6 can. The Series 6 joins other smartwatches from Huawei, Garmin and a handful of other brands in being able to take blood oxygen readings, which could help flag if you're over-exerting yourself if you often exercise at high altitudes.
The Series 4 also came with a redesigned speaker, designed to make your phone calls clearer and your Siri requests more accurate. So you won't get that if you opt for the Series 3.
Other differences between the two latest watches and the Series 3 (pictured above) include:
- an always-on display for the Series 6. The SE and Series 3 will need waking up by raising your wrist or tapping the display
- larger, edge-to-edge display for the Series 6 and SE compared to the Series 3
- cellular versions are available for the Series 6 and SE, but not the Series 3 anymore
- a built-in compass.
One thing that hasn't improved much over the years is battery life - that's actually not too bad for the SE, but is still limited to one day for the Series 6. Granted, the Apple Watch is a hard-working little device that's going to eat a lot of battery. But it's still a pain to keep having to charge it so often - and it could scupper your plans to use the Series 6 for sleep-tracking.
Read our full reviews of the Apple Watch Series 6 and Apple Watch SE to find out what we thought of them overall.

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