If such a thing exist, I'm sure everyone would be asking the same question as you.

No I personally don't think its possible to make free local, interstate, international phone calls without lying to the cell network carrier that your device and what not are actually subscribed to their network.

Even if it was remotely possible, making excessive free calls to anywhere would trigger alerts to cell network carriers and get them to track you down for illegal use of network plus using a hacked device, etc.