WhatsApp Calling has now rolled out to everyone. That means no more waiting to get an invite from someone or tweaking your rooted device to enable it unofficially.
As of today, WhatsApp calling has been enabled by default on the updated WhatsApp version 2.12.19.
To enable WhatsApp calling, all you have to do is install the updated APK over your already installed WhatsApp version or let it update from Play Store.
I had tried the feature when it was still invite only and saw that the call quality was average and not up to the mark as compared to other VOIP calling applications like Skype or Viber. But the feature is still new and is being developed in good hands.
The main interface of the applications is now divided into 3 Tabs: Calls, Chats and Contacts. This has made the calling feature easily accessible.
Go ahead and download this APK: WhatsApp Calling enabled APK.