Transaction cards, systems and methods involving an on-card display and an associated mobile computing device utilized for authenticating transactions are disclosed. In one embodiment, an exemplary transaction card may comprise transaction circuitry configured to conduct purchase transactions involving a mobile computing device coupled to or associated with the transaction card, communication circuitry configured to communicate with a provider of the transaction card, an e-ink display configured to display a QR code on the transaction card for use in authentication, data storage configured to store the QR code, and computer readable media having instructions for initiating a second-factor authentication process and displaying the QR code on the e-ink display to be captured by the mobile computing device and transmitted to a system or server for validating the second-factor authentication process.