(Post updated on January 8, 2021. See section at the end.)

The whole world is using WhatsApp to message each other. I often do too, because I want to inter-operate with the rest of the world.

However, WhatsApp belongs to Facebook.

Although Facebook has promised otherwise (fast-forward a few years: Yes, they did break that promise. See updates at the end of this post.), the temptation to link all of your WhatsApp messages with Facebook logins (a straight-forward process, as they have the mobile phone numbers of a great number of their users) must be quite tempting to the people at Facebook. Imagine how well they would then be able to target their advertising, based on their access to both your Facebook profile and your private WhatsApp messages!

Fortunately, we now have an open source app, called Signal (available on Android, IOS and the desktop), which performs end-to-end encryption on all messages and voice calls that go through it. This means that absolutely no-one is able to read your messages or eavesdrop on your voice calls, except the intended recipients.

My request is that you get your contacts to install and start using Signal instead of WhatsApp wherever possible. At the very least some of our messages will not be accessible to various large corporations and any other prying eyes. If the security argument is not enough for you, there is one more extremely important topic: Signal handles animated gifs better than WhatsApp, at least on Android. (Telegram supports them on both Android on IOS, but it is by default less secure than Signal). See here the results of my experiments:

Animated GIF support (most important feature in any messaging app): WhatsApp fail, Viber fail, Telegram pass, Signal pass on Android.

— Charl Botha 😷 #Masks4All (@cvoxel) January 1, 2016

Updates

January 8, 2021

By now, if you use WhatsApp, the app will have forced you to accept the new privacy and data sharing agreement.

As is explained in this post on arstechnica:

Under the new terms, Facebook reserves the right to share collected data with its family of companies.

In other words, even more of the personal data of 2 billion or so WhatsApp users will be integrated with everything Facebook knows about them and about you, including all of your connections to each other on all of the facebook platforms, including facebook itself, instagram and whatsapp.

Like many of you, to interoperate with the world I do need to keep WhatsApp, but I would greatly prefer chatting with you on Signal.

August 25, 2016

The Verge reported that WhatsApp will now officially begin sharing data with Facebook. They will indeed link up telephone numbers and social networks, meaning that both parties will get a tremendous boost in what they know about you. I don’t want to say I told you so, but I told you so. ;)