One of the benefits to the Nokia Lumia 920 that many of its Windows Phone 8 stablemates don't have is that its outer shell can be removed and replaced. Harking back to the Nineties and the fad for customising fascias and backplates of mobile phones - most notably on the Nokia 5110 - the feature is designed to add a bit of fun to the consumer smartphone market.

Now, to extend that, Nokia is releasing the 3D printing files for the case of the Lumia 820 in order for users to truly customise their phones. Called the 3D printing Development Kit (3DK), the files and templates allow those with 3D printers and the skills to use them to build their own case creations.

Read: Nokia Lumia 820 review

As well as the 3D files themselves, there are also guidelines and suggestions on what materials to use in order to maintain integrity (literally and figuratively) and ensure that the working aspect of the phone is not hampered in any way.

It's all a bit of fun really, and more a proof of concept considering that 3D printing is not cheap at present. But it will be interesting to see what those with the right tools can create.

For the rest of the Lumia 820 owners, a wide collection of swappable cases are already available, including different colour schemes and more rugged shells for greater protection.

To get the 3DK, you need to visit two separate developer pages to download the files. Both can be found on developer.nokia.com.