What a difference a year makes: Apple Watch Series 4 versus Series 3

If you're thinking about upgrading your old Apple Watch to the new Series 4, read and watch our direct comparison first.

This comparison focuses on the new 40mm model, which will be pitted against the 42mm Apple Watch Series 3 so we can see just how much has changed in terms of size, features and functionality.

Design

The new 40mm Apple Watch Series 4 is clearly smaller, closer in size to last year's 38mm model, but the actual viewable display area is greater than the older 42mm versions.

There are changes to the back, too, where Apple built in new heart sensors cased in ceramic.

Aside from that improved back and the larger display area, the most noticeable hardware design change are the speakers. They are much larger and take up the whole side of the Series 4. At least partly because of this modification, the microphone has been moved to the opposite side between the Digital Crown and the side button. Apple says the design reduces echo from the speaker during calls.

Strap in

Even though all Series 4 Watches are larger than the Series 3 and earlier, strap sizes have not changed. If you already have a 38mm Series 3 and bought bands for it, those bands will fit the new 40mm Series 4 perfectly. And it's the same with the old 42mm to the new 44mm model.

Setup

During the setup process, a new screen detailing Heart Health says users will receive notifications when their heart rate is too high or too low.

Explanation of new heart functions on Watch

Similarly, there's also a notification screen detailing the Emergency SOS feature and fall detection feature.

Even with these extra informational screens, setting up the Series 4 is much faster than doing the same on the Series 3.

Face up

The revamped Digital Crown, which now features haptic feedback, is used to scroll through the various watch faces available. The mechanism feels as though it should make little tick sounds as it turns, but it doesn't. Every movement is generated by a haptic engine that sends vibrations through the crown to a user's finger. That motion combines with onscreen visual cues for a visceral experience akin to traditional crowns found in many mechanical watches.

The new crown is also slimmer than the old version. That difference, plus the haptic feedback, makes returning to the Series 3 crown rather disappointing.

Another difference is that the side button is now completely flush with the body of the Series 4, whereas the Series 3's side button sticks out a noticeable amount.

Overall, the new Series 4 looks and feels much more sleek than its predecessors.

Of the new faces, the fire and water designs are perhaps the most striking. As before, Apple actually photographed these: they're not CGI rendered effects, they're shot using real fire and water.

Most of the new faces are available on older Apple Watches once those have watchOS 5 installed. However, instead of using the whole display on those models, they simply fill up a small circle on the screen.

Consequently, all of these new live watch faces — including vapor and liquid metal, as well as fire and water — look much better on the new Apple Watch Series 4 thanks to the larger display.

Potentially the most useful new face is Infograph, which features a slew of different complications. The options can be customized to your liking, and it really looks great, if not quite colorful.

Even though some of those new live action watch faces are available on earlier Watch models, the Infograph face with its cornucopia of complications is not.

Show and tell

See the difference in the faces below. Immediately noticeable are the rounded corners on the Series 4; it looks so much better than the square display on the Series 3.

Sound is similarly improved. The new speakers are claimed to be 50 percent louder, beneficial for both phone calls and the new Walkie-Talkie push-to-talk app. There is indeed an audible difference, as evidenced by listening to Siri's response when asking a question.

The Series 4 also has a S4 system-on-chip that doubles the performance of the Series 3, so everything on the new watch should be snappier.

Thanks to Watch's new all-ceramic back, LTE models boast better cellular reception than before because radio waves are allowed to pass through both the top and bottom of the device.

Have a heart

Perhaps the most impressive feature of the Series 4 is the new ability to take an electrocardiogram out of the box. Though it is restricted in terms of accuracy — equivalent to a one-lead ECG versus the 12-lead medical standard — it's far more convenient than waiting for a doctor's appointment. And speaking of doctors, users can save and send ECG results to care providers. Or rather, they will be able to do so once the ECG feature goes live in a coming watchOS update.

Go buy it

To wrap things up, the Apple Watch Series 4 is really impressive. If you don't already have an Apple Watch and are thinking about buying one, definitely go for the Series 4.

While the Series 3 can be purchased at a hefty discount, the new model is well worth the premium. Collectively, its new features and hardware stack up to the biggest evolutionary step Apple has taken with its wearable product line.

Where to buy

Apple authorized resellers B&H Photo and Abt.com are currently accepting orders for the Apple Watch Series 4. Abt.com will not collect sales tax outside Michigan, Illinois, Indiana and Wisconsin, while B&H will not collect sales tax on orders shipped outside New York and New Jersey*. For a complete list of deals and product availability, please visit our Apple Watch Price Guide.

Apple Watch Series 4 (GPS Only)

40mm (Silver Aluminum, White Sport Band) | MU642LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Silver Aluminum, White Sport Band) | MU6A2LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Gold Aluminum, Pink Sand Sport Band) | MU682LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Gold Aluminum, Pink Sand Sport Band) | MU682LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Black Sport Band) | MU662LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Black Sport Band) | MU6D2LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Silver Aluminum, Seashell Sport Loop) | MU652LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Silver Aluminum, Seashell Sport Loop) | MU6C2LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Gold Aluminum, Pink Sand Sport Loop) | MU692LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Gold Aluminum, Pink Sand Sport Loop) | MU6G2LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Black Sport Loop) | MU672LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Black Sport Loop) | MU6D2LL/A $429.00 ($34 off in tax outside NY & NJ*)

Apple Watch Series 4 (GPS + Cellular)

40mm (Silver Aluminum, White Sport Band) | MTUD2LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Silver Aluminum, White Sport Band) | MTUU2LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Gold Aluminum, Pink Sand Sport Band)) | MTUJ2LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Gold Aluminum, Pink Sand Sport Band) | MTV02LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Black Sport Band) | MTUG2LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Black Sport Band) | MTUW2LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Silver Aluminum, Seashell Sport Loop) | MTUF2LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Silver Aluminum, Seashell Sport Loop) | MTUV2LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Gold Aluminum, Pink Sand Sport Loop) | MTUK2LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Gold Aluminum, Pink Sand Sport Loop) | MTV12LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Black Sport Loop) | MTUH2LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Black Sport Loop) | MTUX2LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Stainless Steel, White Sport Band) | MTUL2LL/A $699.00 ($56 off in tax outside NY & NJ*)
44mm (Stainless Steel, White Sport Band) | MTV22LL/A $749.00 ($60 off in tax outside NY & NJ*)
40mm (Gold Stainless, Stone Sport Band) | MTUR2LL/A $699.00 ($56 off in tax outside NY & NJ*)
44mm (Gold Stainless, Stone Sport Band) | MTV72LL/A $749.00 ($60 off in tax outside NY & NJ*)
40mm (Space Black Stainless, Black Sport Band) | MTUN2LL/A $699.00 ($56 off in tax outside NY & NJ*)
44mm (Space Black Stainless, Black Sport Band) | MTV52LL/A $749.00 ($60 off in tax outside NY & NJ*)
40mm (Stainless Steel, Milanese Loop) | MTUM2LL/A $799.00 ($64 off in tax outside NY & NJ*)
44mm (Stainless Steel, Milanese Loop) | MTV42LL/A $849.00 ($68 off in tax outside NY & NJ*)
40mm (Gold Stainless Steel, Gold Milanese Loop) | MTUM2LL/A $799.00 ($64 off in tax outside NY & NJ*)
44mm (Gold Stainless Steel, Gold Milanese Loop) | MTV42LL/A $849.00 ($68 off in tax outside NY & NJ*)
40mm (Space Black Stainless, Space Black Milanese Loop) | MTUF2LL/A $799.00 ($64 off in tax outside NY & NJ*)
44mm (Space Black Stainless, Sp Black Milanese Loop) | MTUV2LL/A $849.00 ($68 off in tax outside NY & NJ*)

Apple Watch Series 4 Nike+ (GPS Only)

40mm (Silver Aluminum, Platinum Nike Sport Band) | MU6H2LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Silver Aluminum, Platinum Nike Sport Band) | MU6K2LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Anthracite/Black Nike Sport Band) | MU6J2LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Anthracite/Black Nike Sport Band) | MU6L2LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Silver Aluminum, Summit Sport Loop) | MTX72LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Silver Aluminum, Summit Sport Loop) | MU7H2LL/A $429.00 ($34 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Black Nike Sport Loop) | MU7G2LL/A $399.00 ($32 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Black Nike Sport Loop) | MU7J2LL/A $429.00 ($34 off in tax outside NY & NJ*)

Apple Watch Series 4 Nike+ (GPS + Cellular)

40mm (Silver Aluminum, Platinum Nike Sport Band) | MTV92LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Silver Aluminum, Platinum Nike Sport Band) | MTXC2LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Anthracite/Black Nike Sport Band) | MTX82LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Anthracite/Black Nike Sport Band) | MTXE2LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Silver Aluminum, Summit Sport Loop) | MTX72LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Silver Aluminum, Summit Sport Loop) | MTXA2LL/A $529.00 ($42 off in tax outside NY & NJ*)
40mm (Space Gray Aluminum, Black Nike Sport Loop) | MTX92LL/A $499.00 ($40 off in tax outside NY & NJ*)
44mm (Space Gray Aluminum, Black Nike Sport Loop) | MTXD2LL/A $529.00 ($42 off in tax outside NY & NJ*) * B&H will not collect sales tax on orders shipped outside NY & NJ (CO, VT & WA residents, see here).

Add AppleCare+

You can easily tack on an AppleCare extended protection plan to these Series 4 Apple Watches for $79 by selecting the AppleCare option in your cart.

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28 Comments

ivanh 13 Years · 596 comments

About 6 years ago

Why compare just Watch 3 & 4? What about Apple Watch 2 vs 4?

GeorgeBMac 9 Years · 11421 comments

With Apple Watch's main thrust going towards health and fitness I would like to see a comparison done by say, a cross country coach or committed athlete.

Also, I cringe at the statement that the single lead EKG on the Apple Watch provides the same amount of information ("does the same thing") as a 12 lead in a physician's office. They don't put those extra 11 leads on because they're bored. Each lead serves an explicit purpose that no single lead can match. That's not to disparage the AW EKG -- just the claim that its "does the same" as medical grade 12 lead. That's like claiming a pickup truck does the same as a 12 ton dump truck. Yes, they both "carry stuff", but...

Soli 10 Years · 9981 comments

designr said:

This is kinda of typical Apple.

I'll bet if you asked internally this (Series 4) is the watch they wanted to do all along. It just took time to get there.

I think we saw the same with the iPhone 4 or 5.

Where do you make the demarcation point? I'm sure there aspects of this design that never came up in the original meetings because the tech wasn't there or simply no one even considered it. I suspect that a single-lead EKG and a rounded display, weren't on the drawing 7 years ago?

And then there probably things that they had considered in the original meetings that still haven't come to fruition. Waterproofing, GPS, cellular, and an altimeter are all things that didn't make the first model, but could've been on the drawing board from day—but those all in it in now so those would count. We'll have to wait until next year to get better comparisons, but I'd think some non-invasive blood sugar or O2 level checks could've been on the drawing board when they started their multi-year health initiative before the Series 0 was introduced.

Personally, I compare it more to the iPhone 5 or series than to the iPhone 4 since it started with a Retina device, but the display increase in size YoY. Or perhaps even the iPhone X since the display area in relation to its footprint increased in size YoY.

PS: One feature I would've wanted from the beginning but wouldn't have been a possibility is a personal thermostat. "No touch" IR thermostats are commonly used by medical professionals and, so far, I've only seen them used on the forehead. If these can used on the wrist, along with the other functions, it could help tell you when you'll want to sleep (your body temp apparently drops when you're body is getting ready to sleep) as well as help regulate temperatures in your room from a HomeKirt enabled A/C unit, heater, or even a smart blanket. This could even be used (along with the other biometric monitoring) to let you know that you may be coming down with a fever or that you're exerting yourself too hard, even if just to say that you're at risk of passing out or even being able to determine if you're not drinking enough water.

mac_128 13 Years · 3452 comments

designr said:

Soli said:

designr said:

This is kinda of typical Apple.

I'll bet if you asked internally this (Series 4) is the watch they wanted to do all along. It just took time to get there.

I think we saw the same with the iPhone 4 or 5.

Where do you make the demarcation point? I'm sure there aspects of this design that never came up in the original meetings because the tech wasn't there or simply no one even considered it. I suspect that a single-lead EKG and a rounded display, weren't on the drawing 7 years ago?

And then there probably things that they had considered in the original meetings that still haven't come to fruition. Waterproofing, GPS, cellular, and an altimeter are all things that didn't make the first model, but could've been on the drawing board from day—but those all in it in now so those would count. We'll have to wait until next year to get better comparisons, but I'd think some non-invasive blood sugar or O2 level checks could've been on the drawing board when they started their multi-year health initiative before the Series 0 was introduced.

Personally, I compare it more to the iPhone 5 or series than to the iPhone 4 since it started with a Retina device, but the display increase in size YoY. Or perhaps even the iPhone X since the display area in relation to its footprint increased in size YoY.

The demarcation point is unknown to all of us outside. But I don't think it's a big stretch to believe that Apple has a roadmap based on technologies and manufacturing capabilities it knows will be there but aren't yet. Of course plans change as well.

What I meant was that with Series 0 they did what they could but knew they had better plans and ideas that simply weren't possible (at least cost-effectively) at that time but they knew they's be able to get there in a few years. Based on my experience, most products follow this kind of path: First you get something out there (and, granted, Apple's first "something" is often better than other's second or third "something"...but you have lots of plans and ideas for the next few versions...some of which is, in the case of hardware products, waiting on things to be ready. As an example I actually suspect the display was on their minds years ago.

When the Apple Watch came out, I was on record as saying it actually did too much. They could have had a more modest launch, with just as much success, and had more room to add features to promote upgrading. The display ironically was one area I thought they skimped on, especially when Huawei and other Android watches came out with 42mm edge-to-edge displays that same year without significant impact to battery life. That said, this is typical for Apple to hold back on features until they’re ready, and as a result I think we get a much more mature product, with significantly more polish and reliability than Android. I’m looking at the seriously rounded corners of the new design and personally see a round model option coming just about the time the square model hits market saturation and people will be looking to change it up, or stand out from the herd. If that’s what Apple wants to do, this new display makes that easily possible.

ivanh said:

Why compare just Watch 3 & 4? What about Apple Watch 2 vs 4?

Since it's the penultimate Watch released and probably still the most successful series sold by Apple it makes perfect sense to compare the Series 3 to the Series 4. If AI was to do another comparison, based on my anecdotal observations, I'd compare the Series 4 with the Series 0 since I know a lot of people still rocking their original Watch because they were waiting for something more substantial to come along.