I am from India - WhatsApp is messaging here. Scratch that - WhatsApp is communication here. So that’s not really a choice. Maybe you’d have the app for your region unless you’re from USA where I’ve heard it’s iMessage.
In Australia it's iMessage and FB Messenger, mostly. But that's also dependent on where you or your family is from: I came here from NZ, so iMessage/Messenger is normal, but my Indian friends use WhatsApp as a matter of course!
I am not sure there is anything comparable in the US to the way WhatsApp is used in other parts of the world. People just default use SMS texting in the US and Canada. A lot of people do have WhatsApp here though
