Twitter got messaging via its Vine app. Facebook is working on getting voice calls to it’s recently brought WhatsApp but why wait? They recently updated their Messenger app to include free phone calls via cellular or wi-fi. The feather works similar to Google Hangouts. However, to make a call to someone you are not friends with, you have to add them to your address book. The Messenger app already had Voice Calls but now the feature is open to everyone and everywhere. There are so many options out there such as FaceTime Audio, Skype, Hangout, Talkatone, Tango and Viber.
Free Calls: Talk as long as you want and stay in touch wherever you are. (Calls are free over Wi-Fi. Otherwise, standard data charges apply).