Microsoft has launched a phone application called OneApp that it hopes will allow emerging markets - i.e. the third world - to access Twitter, Facebook, Windows Live Messenger, and other applications on their mobile phones.

It's designed specifically for "feature phones", which is an industry euphemism for "phones that are rubbish, but cheap". The app is a tiny 150kb in size, and dynamically launches just the parts of the application that you need for what you want to do.

What that means - and Microsoft hasn't specified this, so we're guessing a little here - is "cloud computing" in the real sense of the term. The application is likely to be just a "thin client" - a stripped down web browser that issues commands to a server and recieves and displays responses.

Microsoft's providing a low-footprint application with javascript and XML implementation, as well as a few starter apps, and then giving an SDK to developers who want to code for it. It's a bit like Adobe's "AIR" application, but for mobile.

The results, Microsoft hopes, will be that OneApp will be the default platform for developers who want to get an application to as wide an audience as possible. The only obstacle preventing that - and it's a big one - is that pretty much none of that audience have OneApp installed, yet.

Apps that are currently available are: Windows Live Messenger, Facebook, TweetLite (a Twitter client), Weather, Celebrity News, an RSS feed reader, a news app, a sports app, a stock tracker, a contacts backup program, a mobile wallet and a small selection of unspecified games.

The App isn't available for download, though. Instead, OneApp will be pre-installed onto handsets by manufacturers like Nokia, Sony Ericsson, and networks like O2 and T-Mobile. The developer kit will be available by the end of 2009 for anyone who wants to code for the platform.

Can Microsoft use this to create a wave of mobile application development for the third world? Or will OneApp in a few years time still be sitting empty, as coders focus their time on building iPhone applications for the western market? Time will tell.