This year, we can expect two revisions to Windows Phone, one minor and one major. But unlike with previous versions, these releases won't necessarily supersede each other and will instead coexist in the market as we head into 2013. And that means that both are quite important to the future of Windows Phone, despite their minor and major tags, respectively. Has Microsoft finally found a recipe for success in the smartphone market?

Windows Phone "Tango"

The first of these releases, code-named "Tango" and expected by mid-2012, is aimed at broadening the Windows Phone user base. It will do so by undercutting the requirements of the current Windows Phone platform to support lower-end devices that can be sold more cheaply in emerging markets. Microsoft is thought to be working closely with its special partner, Nokia, on this Windows Phone version.

The biggest change to Tango, which will likely be called Windows Phone 7.5.1 when released, is that it will lower the platform's memory requirements. It will do so by ushering in a new generation of low-end Windows Phone handsets that utilize just 256MB of RAM, down by half from the 512MB of RAM that's more common today.

But it's not just that these handsets will include less RAM, according to my sources. The underlying OS is also being optimized for the lower RAM allotment, with apps certified for this release being required to use less RAM and other resources, and certain resource-intensive background tasks being disabled.

Developers will be able to target Tango or Windows Phone 7.5 going forward, or both, and users of the new low-end systems will basically be able to access a subset of the existing Windows Phone Marketplace apps selection. (That said, I'm also told that Tango users will be able to browse, but not download, incompatible apps. That's a rather unfortunate prospect.)

This situation will lead, of course, to charges that Windows Phone, like Android, is being fragmented. And while true enough, it's currently unclear how much of the existing Windows Phone apps library will be incompatible with the new devices. I'm told that some high-end games such as "Plants vs. Zombies" won't work, for example, while others such as "Angry Birds" will run normally.

Whatever your feelings on the strategy, it's clear that Microsoft is pursuing a two-prong approach that gives it both quantity (Tango) and quality (Windows Phone 8, see below), albeit in two separate product lines that are familial only in that the available apps are (largely) compatible between the two. Given Windows Phone's relatively low impact in the market so far, this strategy is, at least, excusable.

Developers should receive a new version of the Windows Phone SDK by April, I'm told. This SDK will let developers test apps on both 256 MB Tango devices and mainstream 512MB handsets in emulation. Developers can choose to opt out of Tango going forward if they'd like, though that might not be desirable if these devices sell as well as expected.

I've seen rumors that developers will get support for C++ in the Tango SDK, in addition to supported managed code languages such as C# and Visual Basic, but I've not been able to corroborate that. (And I doubt such support would be tied to a minor OS upgrade such as this.)

More credible are rumors that Tango will support up to 120 different languages, up from 35 in today's Windows Phone versions. I've not verified that either, but it at least makes sense given the target markets. We should know more soon: I'm expecting Microsoft to formally unveil Windows Phone Tango in late February at Mobile World Congress.

Windows Phone 8 "Apollo" Revealed

Thanks to a rather exhaustive leak by the mobility blog Pocketnow, I can now discuss a far more compelling Windows Phone release that will be launched alongside Windows 8. Dubbed Windows Phone 8 and code-named "Apollo," this release is a major one in every sense of the word.

Windows Phone 8 is part of the Windows 8 family of products, and it will share core technologies with its desktop- and tablet-based stable mates—including the kernel, multicore processor support, networking stack, security, and multimedia, according to Windows Phone honcho Joe Belfiore—as well as various user experiences such as the Metro-style UI.

In a leaked video, Belfiore explained that there were two major new functional areas to Windows Phone 8—Scale and Choice andWindows Reimagined—and four supporting functional areas: Seamless Communications, Lights Up the World Around You, Smarter Way to App, and Built for Business. So maybe it makes sense to frame this discussion around those areas.

Scale and Choice

Windows Phone 8 will add support for higher-end processors, including those with dual cores, Belfiore notes in the leaked video. It will also enable up to four different screen resolutions, though he doesn't specify what those are; today's Windows Phone devices support just one, 480 × 800. It will also officially support removable micro-SD expansion for the first time. (And yes, I know that a handful of first-gen Windows Phone devices included this expansion, but Microsoft didn't support it.)

A new feature called Data Smart will help users get the most out of their increasingly restrictive cellular data plans, while underlying changes to the platform will ensure that Windows Phone 8 uses less data than before. The system will use Wi-Fi and not cellular data whenever possible, and a new Kindle Fire–like browser proxy service will make web browsing and third-party app usage 30 percent more efficient.

Data Smart will include a dedicated app for managing data usage and also a live tile with live data usage stats. The Local Scout feature in Bing is being updated to help find nearby Wi-Fi hotspots, and in many regions, cellular data will be automatically offloaded, when possible, to operator-run Wi-Fi hotspots.

Windows Reimagined

The big news for many will be that Windows Phone 8 is officially part of the Windows 8 family of systems. Previously, Microsoft has said that Windows 8 would work on devices with screens as small as 7”, and it appears that Windows Phone 8 will fill the gap for devices with smaller screens.

Regardless of the plan, Belfiore said that the Metro UI used in both Windows 8 and Windows Phone 8 would become "the new familiar," and that hundreds of millions of people will get Windows 8 on their PCs, laptops, tablets, and, yes, phones, in the year after the whole platform launches. (My sources tell me to expect a Q4 2012 launch for both Windows 8 and Windows Phone 8.)

As noted previously, Windows Phone 8 will share key components and user experiences with Windows 8, while some experiences will be custom tailored for the smaller form factor, including Internet Explorer 10, which will ship in a special IE 10 Mobile version just on Windows Phone.

For developers, hardware makers, and device driver writers, the two platforms are so close that those who "are writing apps or device driver writers can reuse, by far, most of their code, making it easy to target both the phone and the PC," according to Belfiore. The grand unification begins.

Windows Phone 8 and Windows 8 will also share several online services, including SkyDrive and Xbox LIVE. SkyDrive will assume a far greater role in this generation, as it will be used for syncing settings and files between Windows 8–based PCs, devices and phones as well as media and other content.

Belfiore specifically mentions storing music and Microsoft Office documents on SkyDrive and then accessing that content "magically" from the phone. He notes that the Windows Phone 8 music experience will be able to stream user-uploaded songs from SkyDrive seamlessly.

Microsoft is also killing off the Zune PC client, which is currently required to sync phone-based photos to the PC and to deliver large software updates to the phone. In Windows 8, this app will be replaced by a dedicated companion app for Windows Phone 8. Presumably, those activities that do require the Zune software today—phone camera downloads and software updates—will also be able to be done through the cloud, but that's not clear.

Seamless Communications

Windows Phone 8 handsets and Windows 8 devices (primarily tablets, but also some laptops) will also include Near Field Communications (NFC) chips and, as important, exterior "tap points" so that users with these devices can share information. NFC, of course, is also used for making secure digital purchases, so Windows Phone 8 will also include an integrated Wallet experience, similar (I imagine) to Google Wallet.

Windows Phone 8 will also support an emerging IP Multimedia/Rich Communications Suite (IMS/RCS) VoIP standard called RCSe. As with Skype, this functionality will be provided as a dedicated app but also with some interesting integration into the relevant platform pieces, such as the People hub contacts management system.

I'm told, however, that Skype will be optional in Windows Phone 8, which I take to mean that certain wireless carriers might choose to leave this feature out of the phones they sell.

Lights Up the World Around You

This rather nebulous category revolves largely around the location-aware features of Windows Phone, a fairly obvious area of functionality for any mobile system. This includes various improvements to Bing and Local Scout, but Belfiore didn't offer much in the way of explanation. I'm told that Local Scout is picking up personal recommendation capabilities, however.

Smarter Way to App

While Microsoft has evolved its app platform through subsequent releases of Windows Phone, adding interesting but limited extensibility functionality in Windows Phone 7.5, Windows Phone 8 will enable a new app-to-app communication capability that appears to be based on Windows 8 Contracts.

It will also add native app creation abilities for all developers, and not just for those who partner with Microsoft, as is the case today. This will help developers more easily port games and apps between Windows 8 and Windows Phone 8, of course, but also with iOS and Android too, Belfiore claims.

The camera app is being thoroughly overhauled in Windows Phone 8 to let third-party developers—and Nokia—dramatically enhance the capabilities of the camera and even take over the built-in camera app, which Belfiore described as "basic." These so-called "lens apps" offer "mind-blowing possibilities," according to Belfiore.

Microsoft is projecting that the Windows Phone Marketplace will have over 100,000 "Mango" (Windows Phone 7.5) apps by the time Windows Phone 8 launches. And all of these will be compatible with Windows Phone 8, which is fantastic. Improvements to the Marketplace experience will surface relevant apps during searches more naturally, Belfiore said, and will utilize Bing technologies to deliver real-time results to users.

Built for Business

One of the most exciting aspects of this system is that Microsoft, finally, is addressing the business market. Windows Phone 8 will "greatly satisfy IT admins" with full support for Exchange ActiveSync (EAS) policies, including full-disk encryption courtesy of BitLocker, and, get this, the Windows 8 Secure Boot feature. And BitLocker will be on by default on every single Windows Phone 8 handset, Belfiore says, so they're secure by default.

Windows Phone 8 will of course include updated versions of the Office Mobile Apps that are tied to the "Office 15" wave of solutions. It will also include enhanced device management and inventory support through System Center, and private software distribution, so corporations can deploy and manage apps inside their firewall.

Folks, this is exciting stuff. And while I might quibble with the two-pronged approach that Microsoft is taking with Windows Phone Tango and Windows Phone 8, there's little doubt that the Windows Phone 8 wave, in particular, will be a huge hit with consumers and businesses alike.

Here, we see the makings of a renaissance for a product line that, frankly, deserves more than the scant attention it's received thus far. With Windows Phone 8, Microsoft's mobile OS is finally poised for success.