Bigger, bolder and more feature-rich than ever, this is a brilliant smartwatch in many ways. It just depends on whether you actually want a digital timepiece - and if you're prepared to pay handsomely for the privilege.

Update: You can still buy the Samsung Gear S3, but it's a similar price to the more recently unveiled Samsung Gear Sport and Samsung Galaxy Watch. We'd recommend looking at the reviews for the Galaxy Watch and Gear Sport before deciding to buy the Gear S3 at a similar price.

The Samsung Gear S3 is a watch that went big in a bid to match the success of the Apple Watch 2 (and subsequently the Apple Watch 3 and 4) - and we mean that literally.

Read more: Samsung Galaxy Watch review

This is a huge timepiece that offers all the features you'd expect from a smartwatch, including GPS, a heart rate monitor, water resistance, NFC, activity tracking, an altimeter and in some cases even LTE.

It pairs them with a great screen, a long-lasting battery and - similar to Apple - a high price, all wrapped up in either a sporty 'Frontier' finish or a smarter 'Classic' look.

That price, and the fact that the Gear S3 runs Tizen rather than Wear OS (and has far fewer apps as a result), could hold it back. That's especially since there are watches on the market like the LG Watch Sport, Fitbit Ionic and the Huawei Watch 2.

These feature-packed watches can even match the high-resolution, circular OLED screen of the Gear S3, and not all of them are as chunky on the wrist.

Samsung Gear S3 Specs Weight: 59g

Dimensions: 49 x 46 x 12.9 mm

OS: Tizen

Storage: 4GB

Screen size: 1.3-inch

Resolution: 360 x 360

Screen type: Super AMOLED

Battery: 380mAh

Processor: Exynos 7270

RAM: 768MB

IP rating: IP68

So what's Samsung doing here? Is there really space for a third smartwatch operating system? Especially when it's on a device that charges a premium?

One of the key selling points is the fact the Gear S3 is compatible with the latest Samsung phones, but also with most other Android phones running version 4.4 of the OS or later, as long as they have at least 1.5GB of RAM.

After launch, the company also announced support for iOS devices, from the iPhone 5 onwards, as long as they're running at least iOS 9 software. The chances are that your current phone will work with the Samsung Gear S3, and, crucially, that you won't be locked in to a particular smartphone operating system or brand down the line.

There's also now the more recent Samsung Gear Sport watch that has a smaller design, but is otherwise very similar to the Gear S3. On top of that, the company has even replaced the Gear S3 with the Samsung Galaxy Watch.

When it comes to using the Gear S3 with non-Galaxy phones, for the purpose of this review we tested it with the Sony Xperia XZ and it performed just fine (apart from needing to install a million Samsung-specific apps to make it work. Come on, do we really need the Samsung timer app just to count how many minutes until food is cooked?)

So the Gear S3 has the right credentials, but is that enough? Or, with a number of functionally similar rivals on the market, is it too little too late for one of the biggest brands in phones, trying to convince us that we all need another smart device?

Out now in both Classic and Frontier flavors

Originally cost $349/£349 (around AU$475)

Now a bit cheaper, but worth considering the Gear Sport or Galaxy Watch

The Gear S3 started life at $349/£349/AU$399, which is expensive for a smart timepiece. We've now seen the price drop to around $280 / £250, which isn't a huge discount considering it has since been replaced by the Gear Sport and Galaxy Watch.

We'd recommend looking at both the Gear Sport and Galaxy Watch before deciding to buy the Gear S3 as the price is similar but this is an older device.

You can also get the TUMI-designed Frontier Gear S3 in the US, with a strap that comes in a "signature Earl Grey colorway and is constructed from an Italian canvas, which features a stainless-steel buckle and stitched edge detailing, is durable enough to resist water, dust, or rough conditions you may encounter on your adventures."

Design

Big and heavy but well-made

Useful rotating bezel and buttons

At 59g the Gear S3 Classic might not sound heavy, but it certainly feels it. And that makes sense when you consider that the Apple Watch 3 weighs anywhere between 26.7g and 52.8g and the Samsung Gear S2 is even lighter at 42g.

It's big on the wrist too, but it's undeniably a high-quality and well put together watch, with some of that weight likely coming from the 1.3-inch screen and the metal frame around it. It's also built to last, with IP68 certification for dust and water resistance.

Samsung has also put some thought into how you should operate the Gear S3, giving you a rotating bezel and two buttons that you can use as well as the dinky touchscreen.

The bezel is the main method of navigation, and one of the standout features of Samsung's recent smartwatches.

It's essentially a dial that you can twist left or right to scroll through screens and lists, or select apps. Weirdly, there's no confirm key though, so to actually launch an app once you've highlighted it you'll have to tap the screen, which is odd when so many of your interactions with the Gear S3 are button-based.

It's not the most fluid way of doing things - although you can set up the Gear S3 to be able to open an app if you hover the dot over the software you fancy.

Of the two actual buttons, both of which are on the side, one takes you to the home screen and your apps, while the other is a back button, and while remembering which is which can take a while, over time you'll get the hang of them.

Flip the Gear S3 over and you'll find the heart rate monitor, which can track your heart beats throughout the day.

This makes it far more viable as a fitness tracker than some smartwatches, and makes it especially appealing to anyone who wants to monitor changes in their resting heart rate.

The Samsung Gear S3 Classic comes with a leather strap in the box. The leather is decent quality, but quite stiff at first, so you'll need to wear it in before it becomes nice and flexible.

The strap connects via a standard 22mm pin, which is a double-edged sword, as although it means there are plenty of alternative strap options, it also makes them a pain to switch over.

That won't be a problem for everyone, but it will be if you're planning to use the Gear S3 as a fitness tracker, since you'll probably have to stick with a sportier, sweat-resistant strap, somewhat ruining the 'Classic' look. You'll also need to invest in a new strap.

If you are looking for something that's as much fitness tracker as smartwatch, you might be better off just buying the Samsung Gear S3 Frontier, as this comes with a slightly more rugged design and a rubberized strap as standard.

It's slightly heavier, weighing in at 62g, but apart from the look and strap of the device there aren't many other differences to the Gear S3 Classic. You can even use the same straps as the Gear S3 Classic if you ever want to go for a slightly more formal look.

In the US you'll also be able to buy an LTE version of the Gear S3 Frontier, and soon of the Gear S3 Classic as well, but mobile data isn't available on either in the UK currently.

Screen

Brilliant 1.3-inch Super AMOLED screen

Always On Display is handy but harsh on the battery

The 1.3-inch 360 x 360 Super AMOLED screen on the Samsung Gear S3 is, unsurprisingly, one of the best on the market. Samsung consistently makes some of the best smartphone screens, and it's using exactly the same technology here, for bright, clear visuals.

Samsung is also hyping up the fact that the Gear S3 uses an Always On Display, the same used in the Galaxy S8 smartphone range. This optionally keeps the screen partially lit up at all times, so you can always see the time, but as you might expect, it's not kind on the battery.

Still, you'll want the screen on as much as possible, because it's beautifully bright and vivid. The circular design is also great aesthetically, though makes reading text at the bottom of the screen trickier than on a square smartwatch face.

It's not that tough to read really, but it looks a bit messy. It would also be good if there was an automatic ‘do not disturb’ (DND) mode here, which you could turn on when you're in bed or the cinema, so you're not constantly flashing like the world's smallest lighthouse with every slight movement.