A nice little app in the iTunes app store called iCall is a nifty little work around for making VOIP calls from your WIFI and 3G iPad. By setting up your account on your iPhone first, and then making a test call from that iPhone while setting up the app on your iPad, you are then free to make calls right from the iPad. It will even show your iPhone number as the caller ID.
There are different levels of accounts available, including a free ad supported(which is what I’m testing with) all the way up to a monthly service charged one.
I had some issues calling from my WiFi network at work (it took forever to find a server), but was able to connect to a MyWi hotspot and had no issues. So your millage may very. The call quality was what you would expect, not crystal clear, but not horrible either. A little echo was present depending who I called, and what kind of hand set they were on.
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