Apple Watch Series 4 comes in new sizes, also adds ECG and huge new screen

Everything you need to know about the new Apple Watch 4
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The Apple Watch Series 4 is here. After the big reveal at Apple's annual September event, the smartwatch successor to the Series 3 is available to buy.

It's Apple's riposte to the Samsung Galaxy Watch, the Fitbit Versa and the sea of Wear watches, and we've already put the new Watch through its paces in our Apple Watch Series 4 review. Our verdict? It's comfortably one of the best smartwatches to buy right now.

Read this: Best Apple Watch apps to download

If you're just looking for a run down of the ins and outs of the new Apple Watch, we've picked out the key highlights about the design, specs, new features and the all important pricing information.

Got any questions about the Series 4? Let us know in the comments section below.

Apple Watch Series 4: Design and waterproofing

Apple Watch Series 4 comes in new sizes, also adds ECG and huge new screen

The Apple Watch Series 4, unlike the Series 3, comes in three different models. There's the standard Series 4, the Apple Watch Nike+ and the Apple Watch Hermès. So there's no pricey ceramic Apple Watch edition to choose from this time. You do still get your pick of stainless steel or aluminium watch case materials in a range of colors, including black, gold and grey. You'll also get your pick of GPS and GPS + cellular models. If you don't care about your Watch working without your iPhone, then the GPS Series 4 could be a better fit.

Essential reading: Best Apple Watch straps to buy

But here's the really the big news on the design front. While Apple has retained the rectangular shape of the Watch, it’s moving up in size for the Series 4. The new Watch now comes in 40mm and 44mm versions, increasing both the smaller and larger designs by 2mm each. And for good reason: to make room for a new, 30%-larger display.

To date, Apple’s done a great job of obscuring the bezel on its smartwatches, but there’s most certainly been a lot of it. The display on the Series 4 is much larger, allowing you to cram even more complications and info onto that screen.

If you're wondering what the bump in size means for all of those Watch bands you've already invested in, don't panic. The ones that work with the Series 2 and Series 3 are compatible with the Series 4, too.

Read this: Apple Watch Series 4 v Series 3

The new watch has had a few other design tweaks, including a new Digital Crown that has haptic feedback and a red circle for LTE models, replacing the red dot of the Series 3. Apple’s also added a new, louder, speaker to the left side of the watch for better quality, while moving the mic away from the speaker to the other side of the watch, which should improve voice quality when on calls and talking to Siri.

Like the Series 2 and the Series 3, the Watch Series 4 is waterproof. It carries the same 5ATM waterproof rating letting you take it for a swim up to 50 metres water depth.

Apple Watch Series 4: New processor, ECG and more

Apple Watch Series 4 comes in new sizes, also adds ECG and huge new screen

The Series 4 is using Apple's new S4 silicon, which packs a new 64-bit dual-core processor that, Apple says, will get you twice the performance we saw on Series 3 – while keeping the same battery life of a-day-and-then-some.

There's also a new accelerometer and gyroscope inside that improves precision. Why is this important? The Series 4 can now detect when you've had a fall. Yes, there's now fall detection. If it detects a tumble, Siri will offers a shortcut to call the emergency services and your emergency contacts. If you don't respond to the alert within five seconds, it will automatically make the call for you.


Another major new feature with the new Apple Watch is the electrocardiogram (ECG) monitor, something that’s more commonly found in professional medical equipment.

This will let you check in on your ticker by placing a finger on the Digital Crown for an ECG reading. You'll be able to take a reading any time and get an alert if the Watch detects any abnormal rhythms – a possible sign of atrial fibrillation.

Essential reading: Why ECG on Watch Series 4 is a big deal

Apple's received clearance from the FDA for ECG and detecting irregular heart rhythms, which is a significant step forward. In fact, this is the first ECG device offered over the counter to consumers. However, FDA clearance is not the same as FDA approval, meaning Apple has proved its device is similar to another "cleared" product on the market. Getting "approval" requires a clinical trial, but is usually for things like drugs and implants.

Apple says the ECG app will come to the Watch "later this year" and only in the US, so the rest of the world may have to wait even longer for that feature.

New heart rate monitor features

The regular optical heart rate monitor is still here, too, with a few improvements. The Apple Watch already alerts you if it detects your heart rate is too high, but thanks to tweaks to the optical sensor on Series 4, Apple can now send you a notification if it detects your heart rate is too low or if it detects abnormal patterns through the optical sensor. To find out more about how HR works on the Watch, check out our Apple Watch heart rate monitor guide.

Apple Watch Series 4: Software and compatibility

Apple Watch Series 4 comes in new sizes, also adds ECG and huge new screen

As has always been the case with Apple's smartwatches, this is one wearable that plays nice with iOS only - that means no compatibility with Android devices. It runs on watchOS and ships with the latest version, watchOS 5. So it builds on existing features that are well liked such as notification support, playing music and tracking sports like running, golf (via third party apps) and swimming.

Essential reading: Why blood pressure is Apple and wearable tech's next challenge

That latest software update brings a host of new features including improved health and fitness features including support for yoga and hiking. It's still well built for run, cycling and swim tracking with plenty of third party apps that can help store all of your data.

Other new features include improved notification and communication support introducing grouped notifications and new Walkie Talkie mode to the Watch for the first time. Siri integration has been enhanced too and for podcast fans, there's now a dedicated app that lives on your Watch Series 4.

Apple's added some new watch faces to make use of all that added space, too, including one that puts the breathing app on the display, giving you quicker access to Apple's mindfulness feature.

We should mention a couple of desirable features that Apple's competitors offer that are not yet properly supported. The first is sleep tracking. Well, there are Apple Watch sleep tracker apps, but Apple doesn't offer its own native app just yet. It also lacks a proper Spotify app, which both Garmin (the Fenix 5) and Samsung watches support. So if you want your Apple Watch Series 4 to play offline Spotify playlists, you're out of luck for now.

Apple Watch Series 4: Battery life and pricing

Apple Watch Series 4 comes in new sizes, also adds ECG and huge new screen

These are two things that we imagine Series 3 owners thinking of making the upgrade will care about. The first is battery life and the bottom line here is that it's not changed for the Series 4. It's 18 hours battery life. So it doesn't quite match what the Fitbit Versa or the Samsung Galaxy Watch can muster up in this department.

As we've already mentioned, Apple has made its smartwatch available in cellular and non-cellular versions, both of which still come with built-in GPS. The GPS model starts at while cellular models will cost at least . To put that into perspective, the Watch Series 3 pricing starts starts at for GPS and for LTE. So you're paying a premium if you choose to upgrade.

How we test

Hugh Langley


Now at Business Insider, Hugh originally joined Wareable from TechRadar where he’d been writing news, features, reviews and just about everything else you can think of for three years.

Hugh is now a correspondent at Business Insider.

Prior to Wareable, Hugh freelanced while studying, writing about bad indie bands and slightly better movies. He found his way into tech journalism at the beginning of the wearables boom, when everyone was talking about Google Glass and the Oculus Rift was merely a Kickstarter campaign - and has been fascinated ever since.

He’s particularly interested in VR and any fitness tech that will help him (eventually) get back into shape. Hugh has also written for T3, Wired, Total Film, Little White Lies and China Daily.

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