The WhatsApp app on Windows Phone has been updated to v188.8.131.52 to support Voice Calling (VoIP calling)
This feature was first released on iPhone and then later on Android back in April. So it only took a couple of months for Windows Phone users to get it now.
It is important to note that the voice calling uses your Mobile/Cellular data and that being said data charges will be incurred if you use it.
If you are cautious of your data charges, your best bet would be to connect to WiFi.
The call button now resides between the attach button and emoji buttons.
One my first try however, call quality was not good, in fact it was very low and the other party couldn't hear me most of the time. And yes, I was on WiFi too.
So let us know, have you tried voice calling on Whatsapp? Do you like the call quality?
Let us know in the comments below...