While we knew it was coming, it looks like Microsoft is officially unveiling the final Windows Phone 8.1 build. As expected, the update will only be made available to those using the Windows Phone Preview for Developers program, and is designed to help developers get to grips with Microsoft’s updated mobile OS ahead of it being rolled out further afield.

After 18 months since the last major Windows Phone update, Microsoft is finally releasing Windows Phone 8.1 to developers today. The software maker detailed the update at its Build conference less than two weeks ago, and it’s clear the version point increment doesn’t tell the whole story. This is a significant update to Windows Phone 8, with new features like the Cortana digital assistant, a new notification center, and skinned Tiles for the Start Screen. Registered Windows Phone developers can now start downloading the update on their devices, but if you’re not a developer there’s still an easy way to get Windows Phone 8.1 before your carrier is ready to start distributing it.