Microsoft isn't saying "Windows Phone 8.1" today at Mobile World Congress, but the company is detailing a few of its features. In an update arriving this spring, Microsoft's Joe Belfiore says the company will "technically" support all existing Windows Phone 8 devices. It's not clear whether carriers will allow Windows Phone 8.1 devices to upgrade, but Microsoft is announcing its own support of existing devices. That's a change from the Windows Phone 7 to Windows Phone 8 release, where existing devices were able to upgrade to 7.5, but not to the latest 8.0 version.
Read more at: Microsoft details Windows Phone 8.1, update coming this spring | The Verge