Microsoft announces Windows Phone 8: It's Windows 8, only on a mobile phone

Windows Phone is finally living up to the name. Microsoft today announced Windows Phone 8, which replaces the old Windows CE core of Windows Phone 7 with the same kernel in its big brother, desktop Windows 8. That means big changes for a critically acclaimed platform that's been struggling in the market.

Microsoft's announcement comes at a developer's conference in San Francisco; we spoke earlier to Microsoft's Windows Phone senior product manager Greg Sullivan to get the scoop.

The new Windows Phone 8 will look and act a lot like Windows Phone 7.5, Sullivan said. You'll still have the live tiles and the same 100,000 apps. The home screen will be enhanced: you'll now be able to fill the screen with tiles if you like. The two existing tile sizes will be joined by a third, smaller tile. Tiles will be resizable, and the OS will be available with a wider variety of colors and themes.

But Windows 8 will be much more tightly tied to Windows Phone 8 than Windows 7 and Windows Phone 7 were, something Sullivan called "bidirectional sharing." They'll share the same kernel, the same file system, and the same basic interface metaphor, Microsoft's new array of sliding tiles which it calls "Metro."

"There's a degree of synergy between Windows 8 and Windows Phone 8. There are also some key differences, which we'll also articulate. But there are key benefits we get from sharing both a core underlying technology infrastructure and a similar UX," Sullivan said.

The new OS will support three screen sizes: the existing 800 by 480, 1280 by 720, and 1280 by 768. Apps will automatically scale to fit, and developers won't have to create multiple versions, Sullivan said. And while he didn't promise any specific processors, he said the new kernel supports up to 64-core processors.

Windows Phone 8 is coming this fall, Sullivan said.

"We're saving the hardware announcements for closer to general availability this fall," he said.

A PC In Your Hand "The underpinnings of Windows Phone 7 are the primary reason we haven't had support for multicore chips ... it's why we haven't had LTE on CDMA, which requires IPv6, and why we haven't taken advantage of the latest generation of SOCs," Sullivan said.

That's all changing now. The new platform will support swappable SD cards for storage, IPv6 which enables CDMA/LTE phones on Verizon and Sprint, and NFC. The file system is now NTFS, and the OS supports enterprise-level, on-device encryption. A new Wallet app will combine mobile payments and the ability to store loyalty cards and tickets, like a mix between Google's Wallet and Apple's Passbook. Chase Bank will be the first major partner for Microsoft's wallet.

Device drivers will have a lot in common with Windows RT tablets, although Windows 8 has greater security so you won't be able to "arbitrarily connect devices," Sullivan said.

The programming tools are changing, too. While the OS will still support Silverlight for existing applications, that's on its way out for new stuff. Now developers can write native code, as well as XNA, C#, and HTML5. They can also now ue the full Microsoft .NET suite instead of the previous Compact Framework.

"The existing 100,000 apps will run unmodified on Windows Phone 8," Sullivan said. "But there will be a raft of new APIs."

Continue Reading: Windows Phone "7.8">

Windows Phone "7.8" This radical reboot leaves existing Windows Phone owners behind; the new kernel won't run on older Windows Phones.

Instead, those older phones will get an upgrade to Windows 7.8, which will offer the new start-screen features - more columns, resizable tiles, new themes - but none of the major changes. The danger here is that as developers code for the new Windows Phone 8 APIs, users on older Windows Phones won't be able to run the new apps. Sullivan acknowledged that may be the case.

Of course, there just aren't many existing Windows Phone owners to bother. Windows Phone has been guttering along at a sub-2 percent market share since it was launched in 2010, and relatively few models have come out recently. The only big, recent hit for Windows Phone was the Nokia Lumia 900 at AT&T - it's those owners Microsoft must worry about alienating.

Sullivan also left open the possibility that Windows Phone 7.5 may live on as an OS for low-cost phones, especially devices with 256MB of RAM like the Nokia 610. Nokia's CEO Stephen Elop recently said that Nokia would try to drive Windows Phones to lower price points, something that doesn't seem to match up with Sullivan's emphasis on higher-end hardware.

"We'll continue to enable our partners to deliver those devices on the 256MB footprint," Sullivan said.

Can Windows Phone Succeed? Windows Phone has been a conundrum so far. It's gotten great reviews and has tremendous owner satisfaction, but just hasn't moved the needle on sales.

Tighter integration with Windows 8 may help Windows Phone succeed, but what the platform really needs is more enthusiasm from manufacturers and carriers. The one truly successful Windows Phone in the U.S. is the one which AT&T was willing to put marketing money behind. Back in May, the president of Nokia North America, Chris Weber, told me that the Lumia 900 had been selling out at AT&T stores.

The platform's fate wasn't helped by a somewhat self-defeating ad campaign selling Windows Phone as the OS for people who don't actually like to use their phones.

Microsoft apparently found the OEM landscape for Windows 8 tablets so bleak that it had to build its own, the Surface. But the phone market is more complicated; OEMs have existing relationships with carriers that Microsoft may want to leverage, and Nokia has a special relationship with Microsoft - as well as its own distribution channels in dozens of countries.

This fall, Windows Phone 8 will join Apple's iOS 6, BlackBerry 10, and presumably Google's as-yet-unannounced Android Jelly Bean on the market. The software is already good; Microsoft needs the hardware and marketing to close the deal.