Simple Steps to activate Whatsapp Calling Feature:
1. Go to Settings2. Application Manager
3. Select Whatsapp and open it
4. Select Clear Data
5. Select Clear Cache (If Highlighted)
6. It will ask you to reset the Whatsapp application to default settings, Press Yes
7. Restart Your Device.
Go to Whatsapp application, it will ask you to enter the phone number. Just follow the onscreen instruction.
You will also get the option to restore the previous messages. (Please take a back-up for all the conversation before performing the above steps).
To activate the whatsapp calling, please make sure that you are using the new version 2.12.5
I have just activated my Whatsapp call





