Recently, Facebook has announced an interesting new feature that allows free US calls to be made to iPhone users across the United States.

Metro, the company that has made this innovation possible, describes this new iPhone feature as “Voice over IP”. Though this technology has been around for many years, VoIP is new to the iPhone and Facebook network.

Now when you use the Facebook Messenger app, people who own iPhones can now make calls to one another as long as they’re on a WiFi network that’s dependable – for free. All you need to do is tap the ‘I’ icon on your phone and select “Free Call”. It’s simple, quick, and will save you serious minutes.

The best part of this new feature is that a phone number isn’t necessary. As long as the user has Facebook a call can be connected. Facebook first started testing this feature in Canada in early January, and now that the program is in beta, the test has been expanded to the US as well.

Similar plans are in the works for Android and BlackBerry as well. The new calling feature does not yet include video.