Viber is a free iPhone app the lets you make free calls to anyone who also has the Viber iPhone application installed on their iPhone. Calls on Viber are free and can be made over WiFi or 3G.
Free. iOS. Connect freely with over 800M users worldwide! Viber is a free messaging and calling app that keeps you connected to anyone in the world through your Internet connection*. It’s the most expressive way to keep in touch with your loved ones and connect with anyone worldwide!