Methods, apparatus, and systems for securing a mobile application are disclosed. Users of the mobile application may be authenticated using a smartphone or other device including a Near-Field Communication (NFC) transfer device capable of NFC communication. An authentication device may be adapted to present itself to the NFC transfer device as an NFC tag and make a dynamic credential available to the NFC transfer device by including the dynamic credential in an NFC tag readable by the NFC transfer device using NFC mechanisms for reading data contents of NFC tags. An access device comprising the NFC transfer device may then provide the dynamic credential to an application server for verification.