Finally, Apple has opened up the iPhone to the running of VoIP (Voice over IP) applications over 3G and EDGE networks.

The possibility of cheaper calls, international or otherwise, at anytime is of course great news for customers, but guaranteed it will shake things up for the networks. At present telco 3 is the only operator to provide support for Skype calls.

The first app to exploit the new found freedom is called iCall (see below), followed closely by Fring. Expect Skype and similar VoIP app developers to follow suit.

With regards to Apple’s new device, the iPad, permissions for VoIP applications help to broaden it’s functions and should go some way in silencing critics who were quick to point out the device’s limitations.

The iPad already has all the necessary tools for VoIP calling – a built-in microphone, speaker, 3G, Wi-Fi, and apps. It is only a matter of time before Apple gives the OK for a camera peripheral for iPad – which should then make iPad a great video-conferencing device.

Meanwhile, in related news Google has decided to bypass any reservations Apple may have about its VoIP Google Voice web app service and instead has launched it as a web app which can befound at http://www.google.com/mobile/voice/.

We’ll have to wait and see the impact these new apps have on the telcos, but clearly one key factor is the reliability of the VoIP apps.

So, we’re downloading the Google app as we write and will follow up with iCal and Fring. Expect verdicts next week.