Overuse of the term "iPhone killer" since Apple's phone hit critical mass, following the release of the iPhone 3G in 2008, has robbed it of most potency and meaning - but it's what Windows Phone 7 was originally intended as. Things haven't quite worked out for Microsoft's smartphone OS yet, but that doesn't mean it isn't rather brilliant.
One of the best things about the HTC Titan, compared to an Android or Symbian phone, is how wonderfully quick it is. The core user interface implements are hardware acceleration, letting it benefit from the handset's graphics power all the time, rather than just when you're trying to play a 3D game or HD-quality video.
It's intensely fast - not just in how quickly it responds to gestures on the super-responsive capacitive touchscreen, but in how fast menus are able to scroll and how snappily animated transitions are. This speed, combined with the aggressive styling of the system, makes using Windows Phone a very refreshing experience - like a pint of ice cold lime juice following days of drinking lukewarm, half-flat coke. Of course, not everyone likes lime juice and not everyone will love the unique look of the Windows Phone 7 interface.
The Titan's home screen is a scroll of very sharp boxes Microsoft calls Live Tiles. These are shorcuts - some animated, some static - to apps, phone features and contacts. They're fairly uniform in appearance, 90 per cent of them adhering to whatever colour scheme's in place, but do helpfully show you updates. The Google Mail and Hotmail tiles show a number, for example, indicating how many new emails you have. It's a notifications system and a home screen all in one, and while it's not very flexible or customisable, like an Android home screen, it's immensely easy to get on with.
You can move Live Tiles around, add and remove them, as well as changing their colour from a selection of 11 hues. Windows Phone is really into uniformity, and you can't pick and choose - it's strictly one colour at a time.
The look can be customised a bit. But only a bit.
At the launch of Windows Phone 7 in 2010, the system had all the rigid styling and speed it has now, but the recent Mango update filled-in the many feature holes that peppered the software. Including multitasking, which is simple and intuitive.
Hold down on the touch sensitive back soft key to bring up a row of snapshots of any running apps, which you then tap on to restore. There are still technical limitations when mulitasking with third-party apps, though. For example, skip to another app during an Angry Birds level and you'll be directed to the initial load screen and main menu upon returning. It's not quite the real deal yet.
Multitasking feels good, but is technically a bit "meh" at the mo
Social networking integration has improved too. You can pre-tag photos of your friends before uploading them to Facebook, and clever messaging updates lets you carry on conversations with people over multiple platforms - IM and SMS, for example. The Mango update is an enrichment that has added depth to the Windows Phone OS, without dramatically changing the basic experience - you can now simply do more within its ornate walls.
Like an ornate, marble-walled museum, though, you can't simply do what you like while inside. To transfer files, most crucially videos and MP3s, you have to use the proprietary Zune software - you're not given access to the file system when you connect to a computer. Using the HTC Titan is a bit like living within a totalitarian regime. Accept its rules and marvel as everything ticks along nicely, the trains arrive on time and the streets are clean. If you like to go your own way, though, you may not find the Windows Phone life so accommodating.
This being a smartphone, these rules can be bent a little with the use of apps.