It seems like each time one of these VoIP apps comes out, it’s all hype. I don’t know what the hold up with Skype is, and Google Voice seems pretty cool yet does not seem to be “blowing up,” but now this Line2 seems to delivering more than the rest when it comes to making calls over the internet via Wifi cell phones.

Line2 gives you a toll free number for people to call you on, free of charge, and it lets you make free, unlimited calls via Wifi. If you’re not in a Wifi zone, your calls go through your normal cell mode. The video below does a pretty good job of explaining how it works.

Line2 iPhone User Guide from Toren Ajk on Vimeo.

It seems like business people really enjoy Line2. The downsides, for me, are that it doesn’t offer text messaging via Wifi (why is this so hard?) and that it costs $15 bucks a month. A big plus, however, is that they offer Line2 for Blackberry.