After rolling out selectively to users worldwide for more than a month, WhatsApp today seems to have started rolling out its voice calling feature to all Android users.
As being reported by users across online forums, the latest version of WhatsApp that is being rolled out through the Play Store is automatically enabling the calling feature for many. For others, downloading the APK from WhatsApp’s website and sideloading it on their device has worked. Selected users are also able to enjoy voice calling on their Android device even though they are on a slightly older build of WhatsApp.
Once the calling service is activated, WhatsApp users will see a new interface in their app that will consist of three different tabs: Calls, Chats and Contacts. They will be able to call any of their WhatsApp contacts over Wi-Fi or 2G/3G without any issues, though the receiver of the call should be on a fairly recent version of WhatsApp.
Previously, WhatsApp users had to receive a call in WhatsApp from someone who already had the calling service activated to activate the service for themselves. However, since the feature has now officially begun rolling out, no such restrictions apply for now.