How Your SIM Card Threatens Your Privacy
Your SIM card does more than just connect your phone. It quietly keeps a record of your daily activities, almost like a diary. It logs the neighborhoods you visit, your late-night outings, and the events you attend. Unfortunately, your phoneโs settings canโt prevent this tracking.
Your SIM constantly communicates with multiple cell towers to maintain a signal. Each time it connects, your unique ID (IMSI) is recorded, building a detailed map of where you go. VPNs and encrypted apps canโt block this kind of tracking.
Jsyk.. Your phone actually has three computers inside, not just one.
The first is the Application Processor (iOS or Android), which is the only part you can actually control.
The second is the Baseband Processor. This hidden chip manages your phoneโs communications and runs its own software, which you canโt see or change.
The third is the SIM card itself. Itโs actually a small computer with its own operating system and can run commands on its own.
Some SIM cards can send texts, start data connections, or share your location without your phoneโs main system telling you. These hidden messages use special encryption and arenโt saved anywhere you can see them.
Also, a VPN does not protect everything on your phone. On iOS and Android, most app traffic goes through the VPN, but some system services might not, depending on how your device and network are set up. Also, parts of your phone like the Baseband Processor and SIM card work outside the VPN, managing network signals and carrier communication directly. This does not mean all your data is exposed, but it does mean a VPN cannot fully protect everything your device does.
Some privacy experts, such as Naomi Brockwell(@naomibrockwell ), have stopped using SIM cards in their phones. Their method is simple.
- They keep their phones on Airplane Mode and only connect to Wi-Fi.
- They use a separate mobile hotspot for the SIM card instead.
- This keeps your cellular identity separate from your browsing and messaging.
Anyways, If youโre in the U.S., the Calyx Institute offers privacy-respecting mobile hotspots with unlimited data through a non-profit model. While they donโt rely on ad tracking like large telecom companies, the service still depends on carrier infrastructure, so itโs more privacy-conscious.
You can delete apps and block trackers, but the SIM card operates at a level you canโt control. The first step is being aware of this. You canโt avoid a surveillance system if you donโt know it exists.