Nowadays, WhatsApp messenger is getting frequent updates. However, it’s not yet rolled out to the Play Store. There are several new additions like- low data usage (to lower the data used during a WhatsApp call). And, if you look at the profile page of an individual, you would get a custom notification option and a mute option. Well, these additions were made with the previous build. The new build 2.12.200 comes with the same features, but the calling UI has got a better materialistic UI.
For both, incoming and outgoing calls, the new UI applies. Here’s the screenshot below:
Before downloading, you need to make sure that you have checked the option to allow “Unknown sources” installation by navigating through Settings->Security->scroll down to find the option. And, don’t forget to uncheck the option after installing WhatsApp successfully.