VOIP calling on the iPhone

not that I know of

According to this Engadget Article VOIP has been demoed on a hacked iPhone by a service called Truephone

Thanks mirza! But it seemed there was no real interface or GUI to make that happen yet right?
There was a comment on engadget recommending other sites like Ekiga and IM+ . Does anybody have any experience with these services?

Wait a few weeks and see what becomes of the SDK that is released this Thursday. I would think that Skype would jump on this soon and that in theory would allow you to call via Skype In/Out using WiFi. To me it seems like a no-brainer for Skype but we’ll see. If not Skype, I’m sure that someone will offer it sooner rather than later. With the iPhone being a “phone”, it just makes sense.

Fring for iPhone is now out, also TruPhone is great…probably better than skype for calls, although you pay a small cost

Right now: a growing array of voip possibilities if you jailbreak, and a few closed-platform options if you don’t (no SIP, I believe—just closed platform like Truphone—and there’s not a native Skype client, but fring uses SkypeOut credits). Another advantage of jailbreaking is that you can force apps that think they need wifi connection to work on 3G or Edge. Of course that’s very useful for voip.