About smartphone monitoring
Smartphones are subject to a great deal of surveillance. Companies like Apple and Google constantly obtain unique IDs assigned to the device (such as Apple ID, Google ID, IMSI, IMEI, MAC address) and use multiple methods like GPS, cellular base stations, WiFi, and Bluetooth to accurately track the user's location.
Furthermore, because smartphones are always powered on, if logged in with the same account as a computer, activities on the computer are also linked as "actions of the same person." This is called "cross-device tracking," where usage information from both PC and smartphone is collected as a single connected dataset.
