“We plan to upgrade all Windows Phone 8 devices to Windows 10 in the future,” Microsoft’s official Lumia account tweeted in response to a question.

Microsoft announced its 'Windows 10' operating system to replace the largely unpopular Windows 8, skipping a number to mark a leap toward unifying the way people work on tablets, phones and traditional computers.

The next version of Microsoft's flagship product, which still runs the vast majority of personal computers and is used by 1.5 billion customers worldwide, is aimed at recapturing the lucrative business market, which generally ignored the new-look Windows 8.
               
Windows 10 will be "our greatest enterprise platform ever," Terry Myerson, Microsoft's head of operating systems, had said at an event in San Francisco.

Only 20 percent of organizations migrated to Windows 8, which was released two years ago, according to tech research firm Forrester. Many PC users disliked the touch-optimized interface and bemoaned the loss of the traditional start-button pop-up menu.
               
He said Windows 10, long known by the project name 'Threshold' internally, represented a new type of system for the company, as it seeks to unify computing as mobile devices proliferate. The name represented that leap, he said.
               
"Windows 10 adapts to the devices customers are using, from Xbox to PCs and phones to tablets and tiny gadgets," said Myerson.
               
Microsoft faces an uphill struggle in reigniting excitement about Windows. With the rise of Apple Inc's iPhone and iPad, and Google Inc's Android devices, Windows no longer plays a central role in many people's on-screen lives.
               
Microsoft Corporation said it would roll out its Lumia 535 smartphone this month with an affordable price tag in its key markets, dropping the Nokia name just months after buying the Finnish company's handset business.

Loaded with its latest Windows Phone 8.1 operating system, the Lumia 535 and Lumia 535 dual SIM will be priced at around 110 euros (about USD 137) before taxes and subsidies, Microsoft said in a statement.
               
The phone will feature a wide-angle 5 megapixel front-facing camera and a 5-inch qHD display screen, the company said.