Research on Capital One’s AirKey identity authentication technology began seven years ago with a focus on whether an NFC-enabled phone possessed the signal strength to communicate with the antenna in an NFC-enabled credit or debit card. Smartphones from different manufacturers have different signal strengths. Capital One determined the best location on specific models of NFC-enabled phones where contactless credit or debit cards could tap and be used to successfully verify the cardholder’s identity. The payment card behaves like a hardware token and provides an alternative to either ema...