WhatsApp allows you to currently have one-on-one voice and video calls. However, that will soon change.
In a posting on the WhatsApp blog, they announced that you will now be able to hold a group video call. In WhatsApp messenger, a group video call can have up to four people.

When you are in a video call with someone, you will see a button saying “add participant”. When you tap this button, you will then have the ability to add people into the call.
This update to WhatsApp messenger is being rolled out to all users at the time of publishing this article.
For many users, this is a welcome addition to the app. There are people that use WhatsApp as their only messaging/video calling app. They will be more than happy with this one.
On the other hand, Skype’s video calling solution allows you to have a video call with up to 25 people in total. Additionally, Apple’s FaceTime app will let you do a group video call with up to 32 people in total. It would be good to see them allow larger group video calls. As such, I am wondering whether WhatsApp is trying to test the waters. Perhaps they are trying this out first before allowing larger group video calls.