Applications for the Apple iPhone aren’t taking up the internet bandwidth and space. Actually only one company have developed an VoIP (Voice over IP) application, the Israeli company fring.

If you haven’t heard about fring, then perhaps you know one of the people behind it – Avi Schechter. He was one of the founder of the once very popular chat-program ICQ. I still remember my ICQ number 7914159, which was stolen by a hacker some time ago.

The idea behind fring is free access to your favourite instant messaging service like Windows Live Messenger, Google Talk or AIM. You can also connect to your Skype contacts and use twitter.

It requires some kind of high-speed connection. That can be either 3G, Wi-Fi or GPRS. I wouldn’t recommend the latter though.

Since you often will use 3G (or GPRS) I would recommend a free data-plan. fring might be free, but the data you are transmitting when talking through Skype isn’t. You’ll still get a bill from your service provider.

I’ve been a happy fring-user for almost a year now. I have it on my Nokia N80IE and Nokia E51. If I had an Apple iPhone I would install it on it too.

As I mentioned fring is the first company to launch a VoIP application for iPhone. You can download fring for iPhone here.

Jonathan MacDonald has written a guide to installing fring on iPhone.

So do you fring while you Skype? Or is it the other way around?