I use WhatsApp every single day. It is how I talk to talk to my colleagues, coordinate schedules, share photos, and keep up with people across time zones. For most of us, it feels like a safe and familiar application. That is why this new activity tracking threat caught my attention.
This is not about reading your messages. Your chats are still end-to-end encrypted which means nobody but you and the other person can read your messages.
The real issue is something called “metadata”. This is the information at a higher level that describes things about you or the messages.
Researchers recently demonstrated a technique that lets someone track when you are actively using your phone, when you go to sleep, when you wake up, and even when you leave the house. All they need is your phone number.
The tracking works by sending invisible probes that never appear in your chat history. You do not see a message. You do not get a notification. But your phone quietly responds with a delivery signal. By measuring how fast that response comes back, an attacker can tell if your phone is in your hand, sitting idle, or offline. Over time, that builds a very accurate picture of your daily routine.
That kind of information is dangerous. It can be used for stalking. It can help criminals time burglaries. It can also make phishing attacks far more convincing because scammers know exactly when you are likely to respond.
What worries me most is how easy this is to abuse. There is no hacking required. No malware. Just a phone number and freely available tools.
The good news is that there is something you can do right now. In WhatsApp, go to Settings, then Privacy, then Advanced, and turn on “Block unknown account messages.” This limits silent probes from people who are not in your contacts. You may already have this setting turned off (I did).
I still use WhatsApp every day. But this is a reminder that privacy risks are not always obvious. Sometimes the most dangerous data is not what you say, but what your applications know about you.