Is that a PC in your pocket?

Mobiles a model for future desktops?

Analysis Mobile phones are not, and never will be, the open and truly flexible platform that desktop computers provide.

Mobile phone manufacturers are constantly telling us that the latest mobile phone can do anything a PC can, but some users are finding that their new handsets are acting in very un-PC ways; refusing to run software a few years old and not letting them develop their own.

While it might seem that phones are becoming less like PCs, it's more likely they are leading the way that PCs are heading.

An application running on a desktop PC can generally, once installed, do anything: it has access to all resources and can do whatever it likes. This criticism has long been aimed at Microsoft Windows, but on any desktop system the owner is the ultimate arbitrator of what should be allowed and the application developer can create applications to do anything.

Unfortunately, the owners have proven their inability to judge the character of applications by the epidemic of malware, viruses and trojans which plague the internet.

The mobile phone companies are terrified that the same problems are going to migrate to their networks, and are prepared to take serious steps to avoid it happening, but if the owner of the phone can't be trusted then who should be?

Attempts to secure Microsoft Windows have constantly been hampered by the need to remain compatible with applications written 20 years ago: Microsoft knows that if it released a version which wasn't backwards compatible their customers would be in uproar, but no such legacy affects mobile phones, at least not yet.

So, at the risk of alienating a few users, Symbian; maker of the most popular smart phone operating system, has released its version 9 OS, which incorporates much greater security at the cost of backwards compatibility. The changes to Symbian 9 are significant in terms of new features, but most applications should only need to be recompiled and tweaked to work, unfortunately (for customers) Series 60 and UIQ (the graphical layers which run on top of Symbian) decided to take the opportunity to update their versions to 3, and make more radical changes that mean applications have to be ported to work properly.

Moving an application onto version 3 of UIQ or Series 60 is estimated (by Garry Partington, CTO of EMCC Software) to take about 20 per cent of the original development effort, and if you want to avoid lots of warnings being displayed to the user then you'll have to get it Symbian Signed too, which will cost you a few hundred quid and take some time.

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