The pressure is mounting on Windows Mobile, Microsoft's increasingly antiquated mobile operating system.

Last week, Google lifted the lid on world's worst-kept secret and confirmed the existence of Android, a mobile OS of its own.

But it's the Apple iPhone juggernaut that's really putting the squeeze on Windows Mobile. Friday's UK launch of the iPhone drew an enormous rabble of both punters and press, despite the fact that the thing is relatively ancient news. It's been available in the US since June.

But is the iPhone really that much better than your typical Window Mobile-powered smartphone? And if so, what does Microsoft need to do to close the gap?

Age old dichotomy

When it comes to iPhone vs. Windows Mobile, it's the same age old Apple vs. Microsoft dichotomy. It's a contest between peerless usability and polish on the one hand and almost infinite flexibility and configurability on the other.

In that sense, Windows Mobile is identical to full-fat Windows for desktop PCs. It's a completely open platform with a huge ecosystem of supporting third-party software. If you need it or can even think of it, odds are somebody has coded it for Windows Mobile.

But just as it shares many traditional Windows strengths, it's also shot through with the all too familiar failings. Whether it's the clunky interface and piss poor usability or patchy stability and questionable security. It's the same story in Windows Mobile as it is in Windows Major.

And just like Windows on the desktop, if you dig deep enough, you'll find some pretty ancient underpinnings. In the case of Vista, its lineage can be traced back to Windows NT. For Windows Mobile, there are some pretty ripe Windows CE gubbins in there. As with Vista's deceptively snazzy 3D interface, the fancy icons of latest Windows Mobile 6 version won't fool you for long.

OS X all over again

The arrival of the iPhone has only made Windows Mobile's shortcomings all the more obvious. It's had a similar impact to that which Apple's OS X originally had way back in 2001; to instantly show the Windows alternative as utterly antiquated and outmoded.

The iPhone's biggest advantage is its interface. The application that arguably showcases it the best is web browsing.