Samsung Gear S2 smartwatch
Samsung has announced the Gear S2 (left) and Gear S2 classic (right) smartwatchesSamsung

Samsung has officially announced the Gear S2 smartwatch. It will go on sale later this year and goes up against the Apple Watch and an increasing range of wearables running Google's Android Wear operating system. Here is everything you need to know about the Gear S2.

1. There will be two versions of the Gear S2

The regular Gear S2 has a sleek, modern design which comes in dark grey with a matching band, or silver with a white band. The bands are made from a similar rubber to those of the Apple Watch Sport, but have a traditional buckle.

Announced at the same time, the Gear S2 classic has a different bezel, a range of faces which resemble a traditional watch, and a leather strap. This model only comes in black, with a matching strap. Samsung says the classic model is for consumers who "prefer more timeless watch design."

2. It has a battery life of up to three days

Where moist smartwatches are dead by the end of one day, Samsung claims both models of the new Gear S2 will last for between two and three full days. Charging is done by placing the watch on an included wireless dock. The watch is designed to be worn at night, and as such there is an app to monitor your health and fitness for 24 hours at a time, including how well you sleep. Running and exercise are logged with a Nike+ app and Samsung's own S Health system, and there is a heart rate monitor on the back of the case.

3. There is a 3G version for making calls

A third Gear S2 has its own cellular connection, meaning it can accept an e-SIM card and make/receive phone calls and text messages. Although, as with LG and its Urbane 4G, it isn't yet clear if this version of the Gear S2 will come to the UK and Europe. This model gets up to two days of battery life, a day less than the non-3G version.

4. The Gear S2 is controlled with a rotating bezel

As well as having a touch screen for swiping and tapping your way through the interface, the Gear S2 also has a unique rotating bezel which is used to navigate through the Tizen operating system. That software, incidentally, is running on a 1GHz dual-core processor with 512MB of RAM and 4GB of storage.

5. NFC will work with Samsung Pay for contactless payments

Just like the Apple Watch and Apple Pay, the Samsung Gear S2 uses an NFC chip to make contactless payments. The system isn't yet live, but Samsung says it is already talking to many banks and retailers, plus it has plans to turn wearables like the Gear S2 into "smart car keys, residential room keys, and remote controls to manage a connected home".

6. The Gear S2 is waterproof

A rating of IP68 means the Samsung Gear S2 can be submerged in a meter of water for 30 minutes - better than the Apple Watch, which cannot be worn in the shower.

7. The screen measures 1.2 inches

It's a perfect circle with a diameter of 1.2 inches, has a resolution of 360 x 360, and a pixel density of 302 per inch.

8. The Gear S2 is slightly thicker than the Apple Watch, but they weight about the same

The Gear S2 is 11.4mm thick and weighs 47g. The Gear S2 classic is also 11.4mm thick, but weighs slightly less, at 42g. For comparison, the Apple Watch is 10mm thick and weighs between 30 and 67g.

We do not yet know the price or release date

Samsung is keeping these important details under wraps for now, but they are likely to be revealed at a media event hosted by the company in Berlin on 3 September. This is also where IBTimes UK will get hands-on with the full Gear S2 range.