they're often used for contact information, especially URLs. however, common programs that can read qr codes can also read the same contact info when presented

they're often used for contact information, especially URLs. however, common programs that can read qr codes can also read the same contact info when presented as text. the choice become presenting the data in a way both the user and the computer can read, or in a way only the computer can read. they do have good uses, but contact info is not one.