AgainstAllAuthority said:
RFID is not able to track you. It does not transmit anything to anyone. It is entirely passive/inactive. What RFID does is it has information programmed onto it when it is created, and that information is saved on there. For a phone, this may be the phone's specific serial number. For cash, it may just be so that there is proof that the cash is real. And for credit card, it just says that the card is real and whose account it is for. But the chip does nothing on its own. It needs to be read by a specialized reader that is designed to interact with the specific resonant frequency of the RFID chip, which is often a very different frequency for different things. And this reader has to come very close to it for it to function. But if you are not anywhere near a reader, there is no way for it to do anything.