Fring, the VoIP client that integrates with various VoIP networks including the ubiquitous Skype, is now available for the 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.
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