Microsoft unveils Windows 8 in challenge to Apple, Google By Dylan Reynolds and Barry Neild, CNN A screen shot of Microsoft's "Metro" user interface. Microsoft has made available a preview version of its latest Windows software Windows 8 upgrade marks computing giant's long-awaited move into tablets Analyst says success of Windows 7 means there won't be stampede to upgrade Barcelona, Spain (CNN) -- Microsoft unveiled Windows 8 for public testing on Wednesday in the hope that it will help the brand win back some of the ground it has been losing to Apple and Google. The new operating system works on tablets as well as PCs and laptops, connecting them via the cloud to give users a more consistent experience as they switch between devices. "It's beautiful, modern, fast and fluid -- it's a generational change in the Windows operating system," Microsoft Windows President Steven Sinofsky said as he launched the consumer preview of the new operating system at Mobile World Congress, in Barcelona, Spain. Read more: Google, the star of the show? Windows 8 scales across devices and screen sizes, Sinofsky said. There's too many hard stops between phones and tablets and desktops. We want to make things more harmonious," he said. The new operating system uses the "Metro" style of software currently being used on phones running the Windows operating system, using tiles on the start-up screen. A new Windows Store, which will be the marketplace for all apps for Windows 8, also launched on Wednesday. Apps will be free to download for the duration of the consumer preview. James Governor, a London-based tech-industry analyst, said Windows 8 was unlikely to galvanize Microsoft's market profile but its entry into tablet technology laid crucial groundwork for sustained relevance. He said the popularity of Windows 7 meant that, as was seen with Microsoft's earlier XP operating system, there wouldn't be intense clamoring for an immediate update. I don't think it's an explosive 'Christ, we've got to have this new release,' he said. There isn't necessarily a pent-up demand for what Windows 8 represents. Read more: Brave new world of mobile medicine Governor said the move into the tablet market represented by Windows 8 marked a key step for Microsoft as it repositioned itself against Apple and Android-powered machines. Microsoft needs to be in the tablet game. It couldn't sit out two or three rounds of tablets without trying to have a more effective play and clearly Windows 8 is a big part of that," he said. In terms of functionality, Governor said Windows 8 suffered from a "weird two-personality thing" as it switched between its user-friendly new Metro interface into functional areas of computing. A lot of people aren't going to be comfortable with that: here is this new Metro personality and then, oh by the way, now I really want some really hardcore web development. I found it OK, but I don't know how it will work with others. Barry Neild contributed to this story from London February 29, 2012 -- Updated 1657 GMT (0057 HKT) Almost all the hot smartphones at MWC run Android, Google's phone operating system. February 29, 2012 -- Updated 1709 GMT (0109 HKT) Mobile devices are being used in radical and innovative ways to modernize healthcare. February 29, 2012 -- Updated 1656 GMT (0056 HKT) Highlights of MWC include a smartphone that turns into a tablet, which then slots into a keyboard, making it a feasible laptop replacement. February 28, 2012 -- Updated 2001 GMT (0401 HKT) The world must act now to prevent a new digital caste system from emerging, Google's executive chairman Eric Schmidt says. February 28, 2012 -- Updated 2118 GMT (0518 HKT) RIM's Rory O'Neill talks about the future of BlackBerry and how cars are becoming more connected. February 28, 2012 -- Updated 1951 GMT (0351 HKT) Waterproof phones are the latest trend. Some use nano-technology, others special seals, to keep water out. February 28, 2012 -- Updated 1031 GMT (1831 HKT) Our phones are becoming uncontrollable monsters, argues 'professional skeptic' Andrew Keen. February 29, 2012 -- Updated 0947 GMT (1747 HKT) Technology that lets you pay in shops by tapping your phone on a hotspot is a hot topic at Mobile World Congress.