Tango allows you to make free phone calls and free video calls over 3G, 4G,
and Wi-Fi. Make calls to any other person who has Tango installed on their smartphone,
tablet or PC. Start a Tango call with just voice, and easily move into a video call
when you have something to share. It’s easy to use, it’s fun, and it works. Tango Features: • Free calls between Windows Phone, Android and iOS phones and tablets, and PCs • Save money with free international calls to other Tango members • Start a phone call with Tango and switch to a video call when you have
something to show by tapping the camera icon • We automatically find the friends that already have Tango • No log in and password - create an account in less than five seconds • Invite your friends by Text and Email • Simple and easy to use Learn more at http://www.tango.me/
one of the apps i will review once i get a nokia windows phone!
if you already have a lumia,
then try it out here