Whatsapp has rolled out new voice calling feature for most of the Android users in the market having latest version of application in the market. The feature was activated from over last weekend. You should have at least version 2.11.528 from the Play Store or version 2.11.531 from the WhatsApp official website.
#Android 5.0 Lollipop operating system was accompanied, or rather preceded, with the release of a set of Android’s “Be Together, Not the Same” Commercials for advertisement on television and other #socialmedia platforms. http://goo.gl/AvT7yh