Windows Phone 8.1 is now available for developers. It features the biggest update in look and functionality to Windows Phone since Windows Phone 7 launched and includes the new Cortana Intelligent Personal Assistant which is said to encompass the entire user experience. Unfortunately, Cortana is a US-only feature for now. Also new is an Action Centre used to navigate notifications better and also an improved start screen tiled interface.
Registered Microsoft developers can get a taste of the future of Windows Phone starting today.