https://www.theverge.com/2018/7/30/17632650/whatsapp-group-video-calling-feature-now-live

Back at Facebook’s F8 developer conference in May, WhatsApp announced that it would be bringing group calling with both voice and video support later on this year. Now, WhatsApp says the feature is live for users around the globe on iOS and Android starting today. The group calling feature supports up to four people simultaneously, regardless of where those people are.

The company says it engineered the feature to work under less-than-stellar network conditions, so you can video chat a friend or family member from a far-flung locale so long as you can get yourself online. Calls are also end-to-end encrypted, like all chats on the platform.