Just days after the launch of Windows 8, Windows Phone 8 was launched at both a San Francisco event in the US and a London event in the UK. Microsoft's partners, including Nokia, HTC and Samsung, will be launching Windows Phone 8 smartphones from early November. See also: What's new in Windows Phone 8? 5 new features in Windows Phone 8
Presenting tonight's Windows Phone 8 launch event, Microsoft's Windows Phone Program manager Joe Belfiore said that "People are the focus of our design", and said that the tie up with other Microsoft products was critical. See Windows Phone 8 review.
"We think Windows Phone is unlike any other operating system out there today. It's also the perfect companion for your Windows PC and Xbox," said Belfiore.
Microsoft's Steve Ballmer also appeared at the Windows Phone 8 launch event, showing off various new Windows Phone 8 handsets from Nokia, Samsung and HTC. He said: "The lines we've seen at Microsoft stores have been heartening. Windows 8 PCs really are the best PCs ever. People love how we've brought together the best of both worlds: work and play, pc and tablet. And today we're bringing in phones."
"If you are one of the millions of people who will be using Windows 8 in the next year, there is really no other phone for you but Windows Phone 8... Log in once and everything you care about will light up on your PC and your phone."
Windows Phone 8 is based on Windows 8 and therefore shares the same Start Screen with adjustable live tiles. The move means that there is effectively a single platform for all Windows smartphones, tablets, laptops and PCs.
New features in Windows Phone 8 include support for multi-core processors, higher resolution screens, microSD cards and NFC sharing. Pre-installed apps will include Internet Explorer 10, Wallet and Nokia Maps.
Microsoft tonight revealed extensions to its Live Tiles interface, as well as new features including a child-safety feature called 'Kid's Corner', a tool called 'Data Sense' that will help keep down data costs, and 'People Hub' - via which groups of fellow users can communicate and share content.
The first wave of devices to run on Windows Phone 8 includes the Nokia Lumia 920, Nokia Lumia 820, HTC Windows Phone 8X, HTC Windows Phone 8S and the Samsung Ativ S. The Nokia Lumia 920 will launch on 9 November exclusively via EE.
The bad news for existing Windows Phone users is that you won't be updated to the latest version because the hardware won't cope with it. Instead owners will be upgraded to a cut down version called Windows Phone 7.8 - luckily this will still include the new Start Screen.
Microsoft will be hoping the Windows Phone 8 alongside Windows 8 will help it in the mobile OS battle with Apple's iOS and Google's Android. See also: 13 new features in Windows Phone 8.