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

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.

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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