It's official: Nokia is dabbling in the world of tablets, with the announcement of the Lumia 2520. The Finnish company, due to be bought by Microsoft at the beginning of 2014, has stepped on board with the Windows 8.1 RT operating system, the same as found in the Microsoft Surface 2, laying to rest any debate around whether the operating system would be a Windows Phone 8 deviant.

With the same software on board, what is it that separates the two devices and which looks to be the better device - Nokia Lumia 2520 or Microsoft Surface 2? The 8.1 RT war in on.

Size and weight: Lumia is smaller, but only just

The Lumia 2520 is smaller and lighter than the Surface 2, weighing in at 615g compared to the Microsoft device's 680g. But both devices are equally fat - or thin, depending on how you look at it - measuring in at 8.9mm.

READ: Microsoft Surface 2 review

The Lumia has smaller dimensions due to a 10.1-inch screen rather than 10.6-inch panel found in the Surface 2, but there's not much between the two: Surface 2 is just 7.5mm wider and 4mm taller than the Lumia, so a lot of the weight comes down to build materials.

Build: Surface is less plasticky

Nokia's Stephen Elop introduced the 2520 as being made from recycled polycarbonate - the black version anyway - which is another way of saying plastic. But, as is typical Nokia style, it's plastic fantastic as there are red, white, cyan and black finishes available.

By comparison the Surface 2 has a sturdier VaporMg build - a bit like aluminium - but is available in only an unfinished grey-silver colour, with a black front panel and bezel surrounding the screen.

Surface 2 also has a built-in two-position flip-stand as standard, whereas the Lumia 2520 has no such feature - you have to use your hands instead or buy the Power Keyboard accessory.

Display: 1080p all round

The Lumia 2520 offers up a 10.1-inch 16:9 display, while the Surface 2 is a slightly larger 10.6-inch 16:9 display. From our time with the Surface 2 we find the widescreen aspect ratio to be bizarre for a tablet device, and Nokia has gone down the same path here - we were hoping for a more conventional paper-like tablet aspect ratio.

READ: Hands-on: Nokia Lumia 2520 review

Display-wise both panels offer Full HD 1920 x 1080 pixel resolutions for stacks of detail and both are IPS panels for wide angles of view. We love the panel in the Surface 2, and have high expectations for the Lumia 2520, even if it's not as resolute as the iPad 4.

Cameras: Nokia wins

Here's an area in which Nokia is really pushing forward. The 2520 comes loaded with a 6.7-megapixel rear camera complete with an f/1.9 Zeiss optic, trumping the Surface 2's 5-megapixel rear camera across the board. Saying that, the Surface 2 is miles ahead of where the original Surface RT's rear camera was, for the simple fact that the original Surface had the worst camera of a modern-day device that we saw in 2012.

Both devices have front-facing cameras too; 2-megapixel in the case of Nokia, 3.5-megapixel for Microsoft. Ideal for Skyping and the like, both at 1080p video quality.

Connectivity: No mobile connectivity for Surface

Another area where Nokia has the winning ticket, thanks to 4G LTE integration for on-the-go connectivity. The Surface 2 doesn't offer connectivity outside of Wi-Fi, a feature that the Lumia 2520 also boasts.

Whether you pick Microsoft or Nokia you do get the best Wi-Fi going, as both offer 802.11 a/b/g/n connections for getting the best speeds available.

Core power

There will forever be arguments about which benchmark said this, that or another processor was better. And that war will rage on between these two devices.

Why? Because the Surface 2 employs Nvidia's Tegra 4, quad-core clocked at 1.7Ghz, whereas Nokia has gone down the Qualcomm Snapdragon 800 route, also quad core but clocked at 2.2Ghz. We're not making any judgement calls here, and it's arguable which will be lighter on battery power drain too.

Software: It's all RT

As we said in our opening gambit, both models will run Windows 8.1 RT, the "lite" version of Windows 8.1. That means no Windows Phone 8 on a tablet.

But Nokia wouldn't be Nokia without its own app integration. In addition to Nokia Camera, there will be other Lumia-only exclusives such as HERE Maps, Nokia Music and the on-board editing tool Nokia Video Director to chop up those movie files. 

Both brands equip Microsoft Office RT, which includes Word, Excel, Powerpoint  and, crucially, Outlook for decent email integration.

Expansion

Nokia comes in and drops out with a 32GB solution for the Lumia 2520. Microsoft offers the same on-board storage solution for Surface 2, but there's also a 64GB version available.

Whichever model you choose, both have microSD card expansion slots to cater for up to an additional 64GB of memory.

Accessories

Surface wouldn't be Surface without accessories. It's one of those tablets that needs a larger ecosystem as, to us, it straddles the tablet-laptop divide. Touch Cover 2 and Type Cover 2 are both excellent ways to expand into a laptop-like experience and there's even that DJ cover for music lovers. 

Lumia is a little more limited, positioning itself more firmly in the tablet space. Unless you buy into the Power Keyboard, which not only provides a keyboard and rear stand support, but also adds an additional 5-hours of battery life thanks to its built-in battery making it a proper laptop replacement, well in terms of battery life. 

Price

At the moment the official UK price for the Lumia 2520 is unknown. If we look at the US prices, however, then the 2520 is a shade more cash: i wi'll cost $499, against the $449 of the  Surface 2.

In UK terms we know that the Surface 2 will cost £359 for the 32GB model. The Lumia 2520's $499 price tag conversion of £278 won't stick either, our guestimate would be for £399 at launch.

Conclusion

If you're after an on-the-go device then the 4G-ready Lumia looks like a more "tablet" tablet, whereas Microsoft's better build and larger screen device sits somewhere between tablet and laptop - it's more of a home device.

We're disappointed that Nokia is running with Windows 8.1 RT, as we were hoping for a Windows Phone 8 tablet device, but that could well be the power of Microsoft. Still, once you get used to handling the software it's not bad by any means, we just don't feel it's up to the same level as Android or iOS solutions right now. But business users might prefer it.

Otherwise these two devices are largely similar. Nokia continues to push its camera, apps, and bright colours, whereas Microsoft might appear to be a more vanilla product, but one that's better built.