watchOS 4 (2017) review

watchOS 4 was announced at WWDC 2017 in June, along with major updates to Apple’s three other operating systems, and in September they are finally launching to the public at large. We’ve updated watchOS on various Apple Watch models to see how well it performs, to try out the new features, and to test out the redesigned interface.

In our watchOS 4 review we report on features, design and speed issues, to help you decide if you should make the upgrade on your Apple Watch. We expect another big update next autumn: take a look at our watchOS 5 rumours article for the latest information on that.

Apple Watch & watchOS History

This is an old version of watchOS that has since been updated. We’re expecting to see Apple Watch Series 10, Apple Watch Ultra 3 and Apple Watch SE 3rd generation, running watchOS 11, launch in September 2024 at the company’s Glowtime event (see how to watch the September event). If you’re in the market for a new Apple Watch, see our Apple Watch buying guide, round-up of the best Apple Watch deals, and advice on whether you should buy Apple Watch now or wait. You might also be interested in what other new Apple products are coming this year, and when is the next Apple event. You can find links to all our Apple Watch reviews below.

• Original Apple Watch (2015) running watchOS / watchOS 2
• Apple Watch Series 2 (2016) running watchOS 3
• Apple Watch Series 3 (2017) running watchOS 4
• Apple Watch Series 4 (2018) running watchOS 5
• Apple Watch Series 5 (2019) running watchOS 6
• Apple Watch Series 6 (2020) running watchOS 7
• Apple Watch SE (2020) running watchOS 7
• Apple Watch Series 7 (2021) running watchOS 8
• Apple Watch Series 8 (2022) running watchOS 9
• Apple Watch Ultra (2022) running watchOS 9
• Apple Watch SE 2 (2022) running watchOS 9
• Apple Watch Series 9 (2023) running watchOS 10
• Apple Watch Ultra 2 (2023) running watchOS 10

Design & interface

The biggest change Apple has made to the watch interface came in watchOS 3, which repurposed the side button: instead of opening the (rarely used) favourite-contacts dial, it now activated the favourite-apps dock, which is great and useful. There’s nothing quite as significant here, although Apple has tweaked the interface in a few noteworthy ways.

A recurring motif (you’ll find it in the dock, Workout app and Music app, for example) is a switch from horizontal- to vertical-scrolling navigation. Instead of swiping left to right with a fingertip you’ll more often be scrolling up and down with the Digital Crown – something we find easier, quicker and more accurate. We don’t yet know if app developers will follow Apple’s lead on this and incorporate vertical scrolling more frequently, but we think it makes sense.

Control Centre

The Control Centre has been redesigned a little, although less noticeably than the one in iOS 11. Mostly things have been just been moved around (Do Not Disturb is a little lower, Silent Mode is now below the fold, and the iPhone pinging feature has earned a deserved promotion) although there’s a new location services icon, and an entirely new entry: torch.

Torch makes the watch face light up bright white – handy when looking for a dropped key in the dark – and you can switch to red or flashing white (good for night-time walks near roads) where appropriate. 

New watch faces

It’s debatable whether this should come under interface or features, but here goes regardless: Apple has added a number of new watch faces in watchOS 4.

Two of these are wholly aesthetic.

There are new Toy Story faces, in the spirit of the Micky and Minnie Mouse faces that have been around since forever but far more involved in practice: instead of just standing there and tapping their feet to the passing seconds, the characters are animated in a wide range of ‘vignettes’. You can choose Buzz Lightyear, Woody or Jesse, but the best option is called Toy Box and randomly alternates between the three, plus Rex the dinosaur, Hamm the pig and the little green aliens.

Yes, this is superficial. But it is also lots of fun.

The second new face type is called kaleidoscope and it’s not quite as interesting. You select one of eight images and a form of kaleidoscopic rotation (‘facet’ is by far the best, in our view); when you glance at the watch face it will rotate slowly, and when you turn the Digital Crown it will rotate faster. This looks pleasant enough, in a trip sort of way, but we got bored of it quicker than the Toy Story one, oddly enough.

The third and last new watch face is a bit more substantial, even though we feel like the execution leaves something to be desired at this stage. Apple calls it the Siri watch face, but it’s Siri in the wider AI sense rather than strictly voice-based.

This face is made up of notifications, arranged according to how important Siri thinks they are to you at any given moment. So there are Calendar and Reminder notifications about upcoming events, nearby weather conditions, frequently used apps and things like that. This is all arranged vertically, of course, and scrolled through using the Digital Crown.

It’s a nice idea, and an experience we expect to improve as the algorithm gets smarter and we all get used to submitting to its wisdom. But two people we know of have found ancient photos of themselves appearing among the notifications for no reason they can fathom, and the rest of us are have yet to be startled by the face’s insight – it’s generally just the next event on the calendar plus an app we’re not interested in using.

A work in progress, then.

New features

While the interface has been tweaked quite gently, there are some significant new features that we think are well worth the upgrade. These are mainly split across the Workout and Activity apps, which we’ll focus on here (although Music has also been redesigned, and some users have complained that they cannot access their full music library from the watch any more).

Workout

Lots of small and a couple of large upgrades here.

As mentioned above, the list of workout types is now arranged as a vertical list. Tapping any of these now instantly starts a workout with the same goal you used last time (open goal, calories, time or distance) for that type. (You can change this by tapping the small icon at the top right of the workout button, but for most workouts you’re likely to save time.)

There’s a new button in the stop/pause/lock screen (accessed by swiping in from the lefthand edge during a workout): a plus sign. When you finish a workout, you can tap this and start a new workout of a different type, and the metrics will be combined together.

Starting a workout now automatically engages Do Not Disturb mode. This will mostly be of interest for owners of cellular Series 3 models, although anyone who does a peaceful workout within range of their iPhone will benefit. (Don’t worry – you’ve still got the option of remaining contactable. To turn this feature on or off, open the Watch app on your iPhone, go to My Watch > General > Do Not Disturb, and tap Workout Do Not Disturb.)

Breaking down to individual workout types, there’s one new type in the main list: HIIT, or high-intensity interval training. This is great stuff, and a properly brutal workout. Then there’s swimming, which has a bit smarter about strokes – it can still work out which stroke you’re doing, but if you use more than one within a workout it will divide up the metrics for each, instead of defaulting to ‘mixed’.

But the upgrade we’re most excited about is something that we won’t be able to test out for a while, because we’ll have to wait for our gyms to update their equipment. It’s called GymKit, and it means the watch can sync with treadmills, exercise bikes and so on.

Using smartwatches on gym equipment is always a hassle (because you have to select and start a workout on two interfaces), inaccurate (because the watch isn’t getting enough information) and pointless (because what’s the point of measuring it on two devices at once?). Except that, if you can make it work well, there’s every point. The gym equipment is best placed to provide accurate data, but the watch is that data’s route into your monthly summary, progress reports and so on. And if GymKit’s syncing is as easy as it should be (i.e. “watch detected, tap here to sync”) then this will be a huge benefit for gym goers.

Activity

Activity, which is the app many watch owners use most of all, gets some smaller tweaks.

The more important again relies on an element of AI, and doesn’t seem terribly sophisticated based on our experiences so far. It’s personalised coaching, and the idea is that you’ll see messages tailored to your goals, performance and level of fitness that give you that extra bit of motivation or advice.

We know that there will be motivational messages when you’re close to a target near the end of the day, for example. But we just keep getting one that observes that we set a new streak record the day before and should try to keep it going.

We’re actually more impressed by something that truthfully takes us back to the realm of superficial graphical changes: there are new animations when you close one or more rings. There’s a sparkly Catherine wheel effect, and another in coloured smoke. None of this really matters, of course, except that getting a cool little graphic when you achieve something adds fractionally but importantly to the sense of achievement you get. This will doubtless wear off after a while, but it’s nice for the time being. 

Performance & compatibility

Apple’s official line is that all models of Apple Watch can run watchOS 4: the only requirement is “an iPhone 5s or later with iOS 11 or later”. But that has not been borne out in our testing.

We’ve installed watchOS 4 on multiple first-gen and Series 2 watches, and in several cases we’ve noticed some degree of performance drag.

On one of the original models it’s been particularly egregious, with apps hanging on a frequent basic and the owner stating that he wishes he didn’t put it on there. (For balance, a second first-gen owner said he hadn’t really noticed a difference in performance – but admitted he’d not tried many apps since updating.)

Our test Series 2 seems a touch slower too. Occasionally it hangs when tapping quickly through menus, and nearly always struggles when trying to rotate the kaleidoscope face just after setting it.

This is a disappointment. The watchOS 2 update actually made existing hardware faster; some original watch owners reported slight slowdown with watchOS 3, but nothing much. But this appears to affect things to the extent that we are unable to recommend that owners of original Apple Watches update to watchOS 4.