Windows Phone 7.5: Microsoft’s Overachieving Underdog

Once upon a time, the name “Windows” stood for something. Several things, actually. It was (and is) the world’s dominant personal computer operating system–a huge, powerful, feature-rich, messy, often infuriating and largely unavoidable piece of software. Windows’ market share has been so overwhelming for so long that there are adults who don’t know what life was like before it.

And then came last year’s Windows Phone 7.

Nominally the successor to Windows Mobile 6.5, the new version had virtually nothing in common with any previous Microsoft operating system. For one thing, it was the darkest of dark horses in the smartphone race led by Apple’s iPhone and Google’s Android. (A recent study puts its market share at an anemic 1.5 percent.) More important, Windows Phone 7 was a spritely, streamlined piece of software with an all-new user interface that was–I’m pretty sure I’ve never applied this word to a Microsoft product before–delightful.

It was also a work in progress. Like Apple, Microsoft followed what I think of as the Benjamin Button school of software design: From the get-go, it gave its new mobile operating system a look and feel that were strikingly mature and thoughtful, knowing it could add more capabilities later. (Google, by contrast, started by packing Android with functions. Only now, with version 4.0 Ice Cream Sandwich, is it focusing on making the software as personable as it is powerful.)

This year’s edition of Windows Phone is version 7.5, also known by the codename Mango. The first major upgrade, it’s got most of the stuff that was conspicuously absent in version 7, including multitasking, cut-and-paste, unified e-mail that puts all your accounts in one inbox with threaded conversations, multiple-calendar support, custom ringtones and much more. For the first time, Windows Phone feels fully baked.

Microsoft’s operating system isn’t on anywhere near as many phones as Android is, but AT&T, Sprint, T-Mobile and Verizon Wireless all offer at least one Windows model apiece. I tried HTC’s snow-white Radar 4G, which is available on T-Mobile for $149.99 with a two-year contract; a $50 mail-in rebate brings the final cost down to $99.99. It’s a nice handset, one that neither mimics the iPhone’s industrial design excessively nor mindlessly follows the fad for massive screens. And like all Windows Phones, it has a dedicated button for the camera, which makes snapping photos a cinch.

I also spent time with Nokia’s Lumia 800, the Finnish phone giant’s first Windows handset. That may seem like a quixotic decision considering that the Lumia isn’t for sale in the United States. But Nokia, alone among the world’s phonemakers, has adopted Windows Phone as its primary smartphone platform, and plans to bring models to the U.S. next year. That could be good news, judging from this curvy, polycarbonate-clad phone–it’s one of the most handsome models I’ve seen in a long time.

So why would anyone bypass the smartphone field’s two obvious choices, iPhone and Android, in favor of a Microsoftian handset? Really, there are two primary reasons why you might–and should–consider a Windows Phone.