It was hardly a secret that Samsung was going to unveil the Gear S3 smartwatch at its Berin Unpacked event on 31 August. But two watches? It was rumoured, and now it's official: the Gear S3 will arrive in Frontier and Classic variants. How, then, do they differ?

On paper the Frontier and Classic don't sound very different: they both measure the same (46.1 x 49.1 x 12.9mm), while the Frontier is a shade weightier at 62g to the Classic's 57g.

The real difference is who these watches are pitched at: the Frontier is the more rugged looking and comes with a rubberised strap as standard, while the more classic looking Classic (clue's in the name, eh?) comes with a black leather strap as standard. However, both models can accept any 22mm standard watch strap - not just those provided by Samsung.

Small details in the finish help define one watch from the other too: the Frontier has larger, textured buttons, which resemble more the sportswatch-like design compared to the more protruding metal buttons of the Classic.

But just because the Frontier looks the sportier model, doesn't mean it comes with a sportier feature set. Indeed both Gear S3 models are IP68 dust-proof and water-resistant, and both feature built-in gyro, accelerometer, barometer, GPS and optical heart-rate monitor.

So both Frontier and Classic are capable of fitness and tracking - a feature Samsung is keen to push with its S Health app.

In some territories a second version of the Frontier will come equipped with LTE/3G for on-the-go connectivity.

But that's not the case in the UK. "Samsung are not planning to launch the LTE variant in Europe at this time", the company told us, when quizzing the appearance of the "LTE/3G" mention of the official product spreadsheet.

Both Frontier and Classic have a 380mAh capacity battery, which is a jump over the previous Gear S2, said to deliver three to four days of use per charge. That's yet to be seen in the real-world, but here's hoping.

The LTE model, however, is unlikely to last nearly as long. Not that we need to worry about that in the UK.

Core to the Gear S3 is its Tizen operating system. Both the Frontier and Classic models shun Android Wear, just as the earlier Gear S2 did - which will also remain in the line-up.

Both Gear S3 models are controlled by a combination of rotational bezel, twin buttons and touchscreen - we actually find it more intuitive and neater to use than Android Wear, which isn't something we would have said of Tizen a couple of years ago.

In its latest form there are more apps then ever before too, including Spotify. So whether you want health, music, social, notifications and other content - or just for the Gear S3 to be your main watch - then both models will have you covered.

Taken as a standalone watch and, despite a 1.3-inch circular digital screen, the Gear S3 Frontier and S3 Classic each offer an always-on display capable of displaying animations and a full array of 16-million colours. That means, even when not active, the watch face is always visible to read the time.

In summary, then, the Frontier and Classic aren't hugely different. Their feature set only differs by the Frontier's addition of 5g weight, its different strap and the more rugged looking, sportier design.

Price point and release date are currently unknown. We'll update as and when the official info is released.