I’ve made a couple of privacy & security related posts already; most of them are kept pretty general, regarding the topic.
I stumbled upon this video today:
I think this is a good point to start for people who still use WhatsApp and are not (as) aware of the huge downsides regarding that application (as us). It explains the dilemma and so many issues that arise when using that app, within 10 minutes.
Here are some WhatsApp alternatives:
I consider many of the alternatives to be very bad choices, as I partially outlined here in this incomplete list of bad alternatives.
However, all the alternatives, even the bad ones, are still better than WhatsApp. Any open source messenger is better than WhatsApp, due to a wide range of reasons, most of them are probably obvious to readers of this post.
So, I’d say, pick any messenger you think is nice, and use that one. If you don’t like it, you can still change, as much as you like, as there is enough to pick from.
As long as you get rid of WhatsApp entirely, you already made the very first right choice!