With Windows Phone 7, Microsoft went from being a non-entity in the world of modern smartphones to becoming an important player. The old Windows Mobile operating systems had their fans, but they weren't as consumer-friendly as the iPhone and Android devices.
WP7 changed all that, bringing integration with Facebook, a clear, touch-friendly user interface, slick multimedia functionality and Xbox Live games and connectivity.
Of course, Microsoft didn't forget its roots, either. There's email and Exchange support, and it's the only mobile OS with official Microsoft Office apps. All of this means there's something for everyone, so we've looked at what's best for each kind of owner below.
And now we're being treated to Windows Phone 7.5 (or Mango to its friends) with a raft of improvements including multi-tasking, improved efficiency and better live tiles than ever before - so check out our updated list of Windows Phones, no matter how you like to use your mobile.
Best for working - HTC 7 Pro
As the only phone operating system with Microsoft Office apps available for it, Windows Phone 7 should be ideal for getting a bit of work done outside the office.
However, a touchscreen software keyboard is the only option on many of the phones currently available, which isn't ideal for writing any longer documents. This is where the HTC 7 Pro comes into its own over the other handsets, offering a landscape QWERTY keyboard for getting your fingers into.
You'll be able to see your documents clearly enough on the 3.6-inch screen, while the usual Windows Phone 7 1GHz processor powers things along pretty nicely. There's also a 5MP camera and 8GB of storage - although we wish that was a little bigger for media viewing too.
Read TechRadar's full HTC 7 Pro review
Best for video - Samsung Omnia 7
With its ability to record and play back 720p video, Windows Phone 7 devices can make for great video players, but it's the Omnia 7 that has the edge, thanks to its AMOLED screen.
It's still got the standard resolution of 480 x 800 in the four-inch display, but boasts vivid colours and incredible deep blacks thanks to the OLED technology.
The Zune software required to load videos is still irritatingly slow, but the screen makes up for it once you get it on the device. With up to 16GB of storage available, you should be able to store plenty of entertainment. There's also a 5MP camera for recording your own videos.
Read TechRadar's full Samsung Omnia 7 review
Best for photos - Nokia Lumia 800
The Nokia Lumia 800 packs an 8MP camera with dual-LED flash, putting it firmly among the best Windows Phone cameras around.
But there's more to cameras than just megapixels, and Nokia obviously know this: the results when shooting are crisp and detailed and even night time shots perform well, with good colours and contrast with and without the flash enabled.
The Lumia 800 also includes a variety of settings to give increased control over shots, as well as options to auto-fix a picture or share it to Facebook directly from the phones image viewer.
Read our full Nokia Lumia 800 review
Best for size - HTC Titan
Given its name, it's no surprise that the HTC Titan is big. In fact at 131.5mm x 70.7mm it's one of the biggest handsets out there, and it makes the most of that real estate with a 4.7 inch screen that packs in decent-looking Super LCD tech to make the contrast ratios look better than other liquid crystal offerings.
Its 480 x 800 resolution provides sharp images and makes it great for video, and web browsing meanwhile is also a breeze as the Titan is able to display a full page on many sites, minimizing the need for tedious zooming and scrolling.
Of course with great size comes (sort of) great weight and the Titan is noticeably heavy at 160g, but we think the trade off is worth it to get a really large and expansive mobile experience.
Read TechRadar's full HTC Titan review
Best for apps - LG Optimus 7
While some Windows Phone 7 handsets differentiate themselves with hardware, LG took the software route. The Optimus 7 boasts two clever apps in particular that neatly expand on what Windows Phone 7 can do.
Play To is a DLNA app, enabling you to stream photos, music and videos between devices. It's a great way to send photos quickly to your TV for viewing, or sending your music to someone else's PC for an evening's entertainment.
The other app is ScanSearch, an augmented reality app that can point you in the right direction for something you want to find if you hold the phone up.
In fact, point it at the sky and you'll even be told the weather forecast. In addition to the pre-loaded apps, there's also an ample 16GB of storage to fill with downloads from the Marketplace.
Read TechRadar's full LG Optimus 7 review
Best for value - HTC Radar
The HTC Radar has the look and feel of a top end handset, with an attractive aluminium body and a reassuring weightiness.
It is also among the first phones to run Windows Phone 7.5 and packs a great keyboard, strong battery life and a respectable 1GHz processor. That might not be the fastest around compared to the 1.4Ghz or 1.5Ghz options on more expensive phones, but rarely shows a stutter in tests.
Despite all this the Radar is available for free on contract from as little as £20.50 per month. It loses out in a few areas, notably its surprisingly limited storage space (just 8GB and no microSD card slot) and the inability to remove or replace the battery.
But for the price it's a very impressive smartphone and one we'd heartily recommend to those working to a budget but still curious about Windows Phone.
Read TechRadar's full HTC Radar review
Best for messaging - Dell Venue Pro
The Dell Venue Pro brings something of the BlackBerry experience to Windows Phone 7, offering a portrait slide-out QWERTY keyboard much like the BlackBerry Torch.
Because the phone is kept in portrait, unlike the HTC 7 Pro, it's easy to see the messages that have gone back and forth in the threaded speech bubble view, and without the on-screen keyboard to clutter things up. It's got an AMOLED screen as well, so videos look great on the large 4.1-inch screen.
Hands on: Dell Venue Pro review
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