Typical transactions are those found when an active device (smartphone) sends out signals and receives information; and when a passive device (NFC tag) simply sends information and does not receive anything other than instructions on what data to reply with. However, smartphones can take on the role of card when they act as a credit card for contactless payments. In this instance the card reader becomes the reader/writer and the smartphone serves as the passive card device.

NFC’s major advantage over other technologies such as RFID is its ability to create peer-to-peer sharing between two phones. The phone making the connection or sending the invitation is the ‘initiator’ and the phone receiving the instructions and sending back information is the ‘target’. Both phones however are capable of both roles by switching back and forth depending on what transmission is being sent.