Rather than wait for iPhones to start shipping with application support, the folks at Fring have decided to release an iPhone version of their IM and VoIP client. This means, for the moment, you must have a jailbroken iPhone to install the software.

Fring provides the ability to make and receive VoIP calls over WiFi, and on non-iPhones, the mobile operator's data network. You also get support for IM as well through the usual networks.

I wonder if Apple is going to allow this app in iTunes once the applications start being official and all.