Windows Phone 8.1 Update 1 Preview Now Available for Download

Notably, the first update to Windows Phone 8.1 is only for developers; although interested Windows Phone users can register to install the latest update free through Microsoft's App Studio program.

Windows Phone 8.1 Update 1 brings an array of features, such as Live Folders, which give users the ability to organise apps into folders on the Start screen of the device; an updated Xbox Music app, which brings background sync of songs collection along with swipe to advance; a Live Tile for the Windows Phone Store, which shows the latest apps or games, and also an SMS interface improvement, which brings the ability to select multiple messages for deletion and forwarding.

(Also see: Microsoft Windows Phone 8.1 review)

Other additions in Windows Phone 8.1 Update 1 includes the new Apps Corner, which offers a special sandboxed mode for certain apps (like a protected Start screen), and enhanced privacy and security features, such as the ability to send and receive data via a virtual private network (VPN).

The first update to Windows Phone 8.1 also expands the availability of Cortana, Microsoft's voice-based virtual assistant, from just the US to other countries including India, China, Canada, Australia and the UK.

Last week, Microsoft had announced that Cortana would be available in China and the UK as a 'beta' version, while in India, Canada, and Australia it would be available as an 'alpha' version.

Originally introduced at the company's Build conference in April, Cortana was first available in the US as a 'beta' and would later be released in more countries. For those unaware, the name Cortana was taken from a popular AI character in Microsoft's blockbuster video game franchise, Halo.

It's worth noting that Windows Phone 8.1 Update 1 will be rolled-out to devices running Windows Phone 8.1 in the coming months.