Fring, the VoIP client that integrates with various VoIP networks including the ubiquitous Skype, is now available for the iPhone (http://www.fring.com/iphone/) - providing exactly the kind of application that Steve Jobs stated wouldn't be allowed.

Fring started out as a mobile client for accessing Skype, though the application now connects to all sorts of networks including MSN, Google pTalk and AIM, thus providing an identity-aggregator for mobile use. It's been available for Series 60 and Windows Mobile for a while, though the company still has no understandable business model as such.

Skype has claimed that creating a mobile client, for anything other than Windows Mobile, is too technically challenging (http://www.theregister.co.uk/2007/01/11/skype_not_ready_for_mobile/) and that they are still working on it; though in reality it's probably more of a problem getting Skype's protocols to work over the mobile networks. Fring cheats somewhat by using its own protocol, which was designed for mobile use, and then providing a gateway into Skype and its brethren.

Fring isn't the only way to get VoIP onto the iPhone, or an iPod Touch (http://lifehacker.com/378511/turn-your-ipod-touch-into-an-iphone), but it's certainly the most compatible. Mobile VoIP provider Truphone demonstrates a client for the iPhone back in September last year (http://www.theregister.co.uk/2007/09/27/truphone_iphone/), though some claimed that the software was not as functional (http://www.theregister.co.uk/2007/09/27/truphone_iphone/comments/) as it appeared. Quite why Fring has been able to launch its client, while Truphone hasn't, isn't clear: Truphone hasn't responded to our enquiry, but it could well be that the company is trying to avoid annoying Apple.

But annoy Apple this surely will - Steve Jobs stated explicitly, when he launched the official iPhone developer's kit, that VoIP applications would not be welcome. Apple is hoping that the vast majority of iPhone users will never unlock their handsets to install unofficial software, but something like Fring could well be the killer application that turns iPhone users to the dark side of unlocked apps and a download-from-anywhere philosophy. ®

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