If you’ve been on the fence about the Apple Watch, I understand where you’re coming from. Early versions were at least disappointing, if not perplexing, limited as much by hardware and software as Apple’s pricing and vision. Holdouts still ask the same question today as everyone did in 2015: If you have an iPhone, do you really need an Apple Watch, too?

For the first time, I’d submit that the answer is yes. The original Apple Watch was a sluggish dud that Apple treated as a full-priced public beta, and its Series 1, 2, and 3 sequels have been iPhone “S”-caliber tweaks that took the first form factor as far as it could go. Three years later, the Apple Watch Series 4 has arrived as the family’s first truly massive upgrade, and finally delivers an excellent end-to-end user experience, notably including health-related features that can’t be found in any iPhone.

Here are the 10 key things you need to know about the latest Apple Watch, which now comes in “40mm” and “44mm” versions starting at $399 for aluminum or $699 for stainless steel. The smaller versions were designed primarily to fit female wrists, while the larger ones come at a $30 (aluminum) or $50 (steel) premium. This year’s most expensive models are $1,499, and all part of the Apple Watch Hermès lineup.

1. Meaningfully bigger screens

Larger screens are the biggest changes to this year’s Apple Watches, and they led Apple to increase the sizes of everything from watch housings to display elements in the watchOS software. Each screen is roughly 30 percent bigger than on the prior “38mm” and “42mm” models, and features rounded corners rather than previously square ones.

Above: Apple Watch Series 4 in 44mm (left) next to Series 1 in 42mm (right).

Image Credit: Jeremy Horwitz/VentureBeat
  • The smaller 40mm model’s screen resolution is now 324 by 394 pixels, versus the old 38mm model’s 272 by 340.
  • The larger 44mm model’s screen has a 368 by 448-pixel resolution, up from the old 42mm version’s 312 by 390.

As a result, the “small” Series 4 model’s screen is actually a hint larger than the “large” Series 3 screen, with a thinner but still obvious bezel between the screen and edge of the case. Apple has kept the OLED screens’ 1,000-nit brightness and pixel density the same as last year’s models.

Thankfully, Apple actually spent the time necessary to revamp its watchOS user interface to make proper use of the larger displays — something it notably didn’t do with the new iPhone XS Max. As you can see on the image above, the larger 44mm model fits more text and better-looking UI elements on the display without shrinking font or image sizes. watchOS has looked cramped for at least two years, but on Series 4 watches, it feels far less compromised.

The most obvious way Apple is showing off the new screens is a set of new watch faces that are either exclusive to Series 4 or better on Series 4 than on prior models. Choices shared between Watches include the beautifully animated Breathe, plus filmed videos of Fire & Water, Liquid Metal, and Vapor. The latter three offer the option of a Series 4-exclusive full-screen mode in addition to a Series 1-3-compatible circle mode, really showing off the different screen sizes.

Apple has also added two new watch faces to all Series 4 watches: the circular analog Infograph, which can be customized with eight customizable complications, and the boxier digital Infograph Modular, with six complications. While neither face is beautiful, they do show just how much available screen space the new Watches have, and provide plenty of customization potential for people who need it. (Apple also added new faces that are exclusive to the latest Nike and Hermès versions of the Watch.)

There are two small issues with the new screens. First, touch sensitivity extends out to the edges of the display, but isn’t wholly reliable at the upper left corner, which sometimes requires a few taps rather than just one. Elsewhere on the screen, however, everything’s just fine, and deeper “Force Touch” presses on the display feel more effortless and responsive than before.

Second, the color rendition on the new displays doesn’t seem to be as vivid as on prior models, though this could be anything from the screen coating to a difference in the new model’s OLED display. I noticed this difference particularly on the new Fire & Water watch face, where the fire didn’t have the same orange warmth as on my prior aluminum Apple Watch. It’s not a huge problem, but I slightly preferred the colors on the prior screen.

2. Taller, thinner housings

To fit the new screens, Apple made the Series 4 Watches a little taller and wider, a difference you’re likely to immediately notice on your wrist. Here’s how each version changed:

  • The smaller 38mm model measured 38.6 (H) by 33.3 (W) by 10.5-11.8mm (D), and has evolved into a 40mm version measuring 40.0 (H) by 34.0 (W) by 10.7mm (D).
  • The larger 42mm model measured 42.5 (H) by 36.4 (W) by 10.5-11.8mm (D), and has evolved into a 44mm body measuring 44.0 (H) by 38.0 (W) by 10.7mm (D).

While Apple kept the height and width constant in all of its past watches, it thickened the later models to provide extra battery space. The Series 4 models aren’t the thinnest ever, but rather are on the thinner side of the family’s historic range. They’re only an imperceptible hair thicker than Series 0’s and Series 1’s 10.5mm bodies.

Apple also tweaked the sides and back of the Series 4 casing. The Digital Crown now has a red ring on LTE models rather than a bold red circle, and uses the Taptic Engine for haptic clicks when you turn it. It doesn’t keep up with the actual motion of the dial, and therefore isn’t as exciting as expected, but it feels better than nothing. The side button is now flush with the rest of the casing rather than protruding, and the microphone hole is now between the controls rather than next to a speaker.

Series 4 retains last year’s 50-meter depth of water resistance and submersibility, enabling it to be worn pretty much anywhere — shower, pool, rainstorm — without fear of damage. As with the Series 2 and Series 3, a raindrop icon in the watchOS software lets you clear out the speakers if they become waterlogged.

Additionally, Apple has dramatically overhauled the health sensors as discussed in detail below, a change that makes the bottom of the Watch look very different than before. Even the aluminum-bodied Apple Watch models shift from plastic backs to the ceramic and sapphire used in steel models.

Last but not least, Apple has introduced a gold stainless steel option for the first time. It matches the iPhone XS and iPhone XS Max with a rose gold color that tends to show as pink in most lights, but can lean more heavily yellow depending on the lighting and angle it’s viewed at.

Golden steel joins silver or space black steel at $300 premiums over the base models, since you can only get steel in Series 4 models with cellular functionality. For the base $399 (40mm) or $429 (44mm) prices, you can choose from silver, space gray, and gold anodized aluminum options. There’s no ceramic or actual gold Series 4 model this year, but Apple offers Nike+ models at the same prices as aluminum Watches, and fancy Hermés leather banded versions starting at $1,249.

3. Continued compatibility with bands

One piece of great news for prior Apple Watch users is continued compatibility with past Watch bands. Despite the housing changes, prior 38mm bands work with the 40mm Apple Watch, and 42mm bands work with the 44mm Apple Watch. The new watch bodies taper to let Apple’s prior band lugs look perfect with the larger bodies.

Apple has not yet introduced any major new band designs for the Series 4 Apple Watches, apart from making seasonal color changes, and continues to offer various band and Watch bundles — plastic Sport bands and fabric Sport loops are the lowest-priced default options. If you’re a Nike fan, Apple touted the addition of reflective thread to the Nike+ model’s fabric loop as the biggest band change this year.

4. Improved health and motion sensors

Every Apple Watch since the original has featured a respectably accurate optical pulse sensor, as well as a gyroscope and accelerometer for tracking movement. Last year’s model added a barometric altimeter to measure elevation, which later saw a software update to support improved skiing and snowboarding tracking.

This year, the accelerometer has doubled in sensing power (from 16 g-forces to 32), the gyroscope has been “improved,” and a second-generation optical pulse sensor has been installed. Apple says that these features will cumulatively allow the Series 4 to offer wider or more precise measurements than before for activity and workout tracking, though in practice, the differences aren’t fully obvious yet.

One noteworthy addition is an accidental fall detection system, which can sense and react to the unusual collection of unnatural motions involved when someone tumbles to the ground. If a fall is sensed, Series 4 can be set to automatically call emergency services after 15 seconds pass without a response to a wrist-based alarm, but as the feature’s not perfect at detection, it’s not mandatory or guaranteed to work. Even so, it’s turned on by default for users aged 65 or older, and will be of particular benefit to users with mobility issues. Like the Apple Watch’s other health features, it’s a very welcome addition even if it won’t be used by everyone.

Above: Apple Watch Series 4 (right) completely redesigns the health sensor array on the bottom of the watch to incorporate an ECG electrode and new optical heart rate sensor.

Image Credit: Jeremy Horwitz/VentureBeat

On a similar note, the marquee addition to Series 4 is a feature that isn’t being unlocked until “later this year” in the United States — and who knows when elsewhere: an electrical heart sensor with an ECG app. An ECG is a recording of the way your heart is beating, displayed in a shape that a technician or computer can recognize as normal or abnormal. If the shape is consistently normal, great. But if it’s abnormal, it’s time to visit a doctor.

Speaking from personal experience, it’s an understatement to call this feature potentially life-changing, as it will enable users to learn about and manage potentially latent heart conditions that are waiting to unexpectedly strike them down. My wife and I discovered three years ago that such a condition runs in our family, and if we’ve learned anything from that experience, it’s that no one should assume that his or her heart is working perfectly.

Series 4’s heart sensors can collectively alert you to abnormally high, low, or irregular heartbeats, giving you the opportunity to take action before tragedy strikes. We’ll have to see how all of the heart functionality works together when it’s unlocked, but if it’s like prior Apple Watch health tracking, it will only get better over time. Even if there was no other reason for an iPhone user to consider an Apple Watch, its growing collection of health features would make the purchase worth considering.

5. Little audio improvements

The new Apple Watches feature two changes in the audio category: Speaker volume has increased a hint, and the microphone location has been shifted from the left to the right side, a change designed to improve voice input quality.

In practice, while I was expecting to see fairly large changes here, I found that the Series 4 generally sounds the same as older Apple Watches when used as a speakerphone — the benefits, if any, are in reducing feedback that Siri might hear during requests for assistance, and slightly improving echo cancellation during phone calls. Unfortunately, while Siri seemed to make fewer errors in identifying what was being said, it continues to suffer from the same old issues in actually doing anything with requests.

6. A faster S4 chipset and more capacity

Series 4 includes a couple of substantial chip changes. First, it includes an Apple S4 processor, the first 64-bit CPU in an Apple Watch, which promises up to twice the speed of last year’s S3. This is the third time Apple has roughly doubled the prior generation’s speed, a change that matters for one key reason: Early Apple Watches were deadly slow — so slow that people didn’t want to use some of their features because they were so unresponsive.

That started to improve with prior Apple Watch CPU upgrades, and with Series 4, performance is a non-issue. There aren’t any benchmarking apps for the Apple Watch, so the only ways to indirectly measure system performance are personal observations and Sunspider tests, both of which somewhat quantify the improvements — they’re certainly there, and obvious across a variety of usage scenarios. Here are a handful.

  • The Watch cold-boots in around 30 seconds, way faster than before.
  • Siri generally takes much less time to process what you’re saying, though it will still frequently disappoint you by failing to be able to do anything with your requests.
  • Tapping on a random app typically brings up a usable screen within a second, unless the app depends upon an internet connection for its initial data, which may take an extra second or two.
  • Transitions between anything — watch face to app screen or dock, watch face to Control Center, watch face to Notifications — tend to be pretty much instantaneous.

Additionally, Series 4 now features 16GB of storage capacity across all models. The standard Series 3 (and all prior Watches) had 8GB, with 5.2GB of usable space, which was enough for a small assortment of apps and a playlist or two of synchronized music. Last year’s more expensive cellular version came with 16GB of capacity — 12.6GB usable — so now everyone has the extra space.

Unless you really want to load up your Watch with apps or music, the capacity change probably won’t mean much to you, but it’s nice to have enough room for pretty much anything the Watch might need at this point in time. The fact that the Watch performs so much better might encourage people to actually start using previously developed apps, assuming they haven’t been discontinued — unfortunately, many have.

7. Faster wireless and tweaked cellular

Apple launched the first Apple Watch with support for two wireless standards: 2.4GHz 802.11b/g/n Wi-Fi, and Bluetooth 4.0. Wi-Fi has remained the same from generation to generation, but the Bluetooth was bumped to version 4.2 in the second year, and Series 4 takes a further step forward to Bluetooth 5.0. (That’s thanks to an updated Apple S3 wireless chip.)

As a practical matter, you might notice this change if the Apple Watch is paired with another Bluetooth 5.0 device or accessory, but there aren’t many of them out there right now. That said, owners of 2017-2018 iPhones may notice a difference during downloads, such as syncing content to the Watch or updating watchOS, which typically (and surprisingly) uses Bluetooth.

I had a series of Bluetooth-related problems when I tried to use an older Watch backup to “restore” the Series 4, but wiping the backup and starting fresh — a fairly easy and comparatively painless process with the Watch — made a world of difference, even though it should have been unnecessary. With watchOS 5 running fresh, the Bluetooth sync process to add a large number of apps was blazingly fast, as were transfers of screenshots and other files that were getting hung up with the initial restore.

It’s likely that most of the problem was iOS/watchOS software-related, but having Bluetooth 5.0 hardware on both sides probably helped with speed once the issue was resolved. Whenever Bluetooth 5.0 AirPods come out, they may exhibit better wireless range and/or signal reliability with the new Apple Watch, as well.

Starting with last year’s Series 3 model, Apple began to offer two versions of the Apple Watch: a “GPS” version with GPS hardware, and a “GPS + Cellular” version with both GPS and an LTE modem. There’s a $100 premium for the cellular model, and increasing carrier support for the functionality, which for $5 to $10 per month bonds the Watch to your cell phone number, letting you make calls and access your phone plan’s data when you’re not carrying your phone with you.

Apart from battery performance (below), data services and calling work as you’d expect on the Watch: OK. You can access your contacts list or a dialing keypad for calls, and stream the same types of data over cellular that you’d normally be accessing over your phone’s Bluetooth or home’s Wi-Fi connection. But unlike a phone, you’re not going to be making super-long calls or using a ton of data from your watch. For that reason, if you’re thinking of buying a Cellular model, I’d suggest you take advantage of a carrier deal, because at $10 for minimal Watch service, they’re going to be taking advantage of you.

For this year’s cellular versions, Apple didn’t make many promises about the Series 4 beyond to say that the new watches have an improved antenna design and support more bands than before. The reality is a little more complicated. There are now two cellular Apple Watch models rather than three: one North American model, and one international version that includes support for mainland China rather than requiring separate Watches. Both the North American and international versions of the LTE Watch actually drop one band — 800MHz UMTS — but the international version adds LTE band 41, TD 2500MHz.

What this all means for average users is simple: The last cellular Apple Watch wasn’t a “world” model, and this one isn’t, either — U.S. and Canadian users in particular shouldn’t expect to get cellular service with the Watch overseas, or vice versa. Thanks to the Watch’s exclusive use of eSIM technology, there’s a day when this could change, but don’t hold your breath for that to happen soon.

8. Continued battery disappointments

Every year, the Apple Watch battery story is the same: Apple promises 18 hours of life, which is good for a typical day of use between charges. The story’s the same this year, albeit with two small changes — the phone promises an hour less of talk time when used as a Bluetooth speaker phone, and an hour more of workout tracking time.

While it would be unfair to describe Apple as having made zero progress on this front for three years, the reality is that the Apple Watch’s one-day battery life and one-hour cellular talk time are far below what most people would prefer, even if that’s what customers come to expect from Apple. Users shouldn’t have to worry about whether a watch will keep working through the night if they have to make a 30-minute phone call.

Having used prior versions of the Apple Watch, I can say that if your use of Series 4’s most power-draining features is light, and you’re not using the Cellular model, you’ll be able to go for a day and a half between charges. But there are competing watches that will work without compromises for two to five days. With the Cellular Series 4 Apple Watch, battery drain will likely be higher, and on the 44mm model, the 18-hour/one-day estimate is fair.

(Update on October 9 at 10:20 a.m. Pacific: After two weeks of testing non-cellular and cellular models, my feelings about Series 4’s battery life are somewhat more nuanced. While the first days after each version was set up appeared to be particularly draining, both watches settled into more consistent patterns: the non-cellular model could stretch to two full days of use if you’re not working out or using the Bluetooth phone feature, while the cellular model showed stronger drain that varies based on its proximity to an iPhone. Battery life meets Apple’s claims, but if you’re not pushing the Series 4 particularly hard, you may well find that it lasts a lot longer than expected.)

Like its predecessors, the Apple Watch Series 4 ships with a wireless inductive charging puck that has a USB-A connector on the other end. Though Apple separately certified this year’s chargers — the first time it has done so since 2015 — they superficially appear to be unchanged from before, so whatever’s new is unclear. As before, the Watches are super-easy to charge, though a charging stand is strongly advised for convenience.

9. What’s obviously missing

At this stage, the Apple Watch has several obvious flaws: battery life, limited watch faces without screen persistence, and responsiveness. The platform would be markedly better if you could use it for multiple days between charges, keep your choice of clocks on the screen at all times, and rely upon Siri to work reliably and instantly.

This isn’t to say that the Series 4 Apple Watch hasn’t improved over its predecessors — it has. To address some user demands for more clock options and “better Siri,” Apple updated watchOS some time ago with a Nightstand Mode to let the Watch serve as a bedside clock, and in watchOS 5 enables Siri to be more easily triggered with just a twist of the wrist.

But these improvements haven’t really expanded the Watch’s utility to the point it should be at by now. There is no good reason that the Watch should still be confined to Apple’s own set of Watch faces, which remain extremely limited despite adding six (or seven, depending on the Watch you purchase) new options for Series 4. It’s also amazing that Apple doesn’t offer a basic, one-color persistent clock option for users who want it. And Siri still stinks.

Virtually everything Apple has engineered into Series 4 appears to have been geared towards getting it to complete the original model’s vision — specifically, what Apple wants it to do — rather than what mass-market users have been asking for. Focusing on nearly-one-day battery life has killed the Watch’s ability to be worn at night as a sleep tracker, and limited its ability to be used as a “smartwatch” for more than a day between charges, depending on how much you use the battery for workouts or phone calls. Once Apple addresses these issues, the Apple Watch’s potential will be limitless.

10. Pricing and conclusions

After several years of iterative improvements, the Apple Watch Series 4 is finally worthy of being called great: It’s pretty much everything that people would have hoped for the original model to be back in 2015, and then some. The larger screens alone dramatically improve reading text and using apps, while the new processor and sensors make interacting with the watch feel fantastic. You’ll be reminded of the scope of improvements virtually every time you look at a watch face.

This year’s Watches are a little more expensive than last year’s, but unlike the iPhone XS, they feel worthy of a small premium — even if they’re belatedly delivering on the potential they had several years ago, an aluminum Series 4 will feel like a worthwhile investment by the time you’re done with it.

On the other hand, the stainless steel Apple Watches have crossed the line into “too expensive.” Requiring customers to buy cellular functionality to get a stainless watch is a cruel trick, and for those of us without a need to pay recurring fees for a watch, a waste of money. Thanks to mediocre cellular battery life and still-limited data functionality, there isn’t yet a mass-market need for an LTE watch. If those issues are addressed, that could change over the next few years.

If you’ve been holding out on an Apple Watch, I’d advise you to strongly consider giving the Series 4 a shot — unless you need a watch that you can wear overnight. In that case, hold out for a year: Even if that improvement’s not next on Apple’s list, many Apple competitors (including Samsung and Qualcomm) are working on solutions that feature improved battery life as a key differentiator. We’ll just have to see whether they deliver overall experiences as wide-ranging and refined as the Apple Watch Series 4.