I found the Hey there! You are using WhatsApp: Enumerating Three Billion Accounts for Security and Privacy a fascinating read. Unfortunately, it confirmed once more my perception of how Meta couldn’t care less about users' personal information. How is it possible that a single server could download all that data? Unbelievable!

Because of my love for numbers and graphs, I also spent a lot of time on the ones in the paper that, by the way, go way beyond WhatsApp. For example, the one below has to be the best representation so far of the Android-iPhone market share. I’m not a statistician, but I believe a 3.5-billion sample can generate a pretty accurate representation of reality.

2025-11-22 at 15.47 WhatsApp users — Android-iOS.png

To be completely honest, I thought Apple had a bigger market share in both the US and Europe, and it would be cool to see how things changed in a year or two. Meta said they patched the data downloading issue, but given their history of data leaking, I’d say there’s a good chance we’ll be able to see an updated graph in the near future.