Hmm, Yes This is true that you can make Free international Call or National Call,And Even can send Free SMS. ANY Country User Can Use this Service
For Free Calling you just have to Go to this LINK and sign Up and go to Free SMS and Call.
Then Verify your Phone Number and send SMS or call your friend National or Internationally or to check you can also call your Number but it will Show busy :)
This Service is offered by Ibibo.com where you can share,play and do lot of things.
So go and Make a Call
And Remember the more you invite your Friends the more you get the free calling Minutes. Default Free Calling Minutes are 3 min and for every Person You refer you Get additional 3 Min .
For Eg: If you Invite 10 Friends you get 30 Free calling Minutes .
So Enjoy Calling.