— Emanuele (@mancae90) June 12, 2015
Latest WhatsApp Beta screenshot reveals a new feature. In the above screenshot you can notice the missed call and incoming message notifications appearing on the top next to WhatsApp. The Beta build in question is 2.12.44.
Before this WhatsApp Beta build 2.12.38 brought VOIP calling to Windows Phone. It is not clear at this moment though when one can expect the feature to arrive with the stable version.
— Emanuele (@mancae90) June 10, 2015