System comprising: - a dynamic transaction card (120,200,300) that includes: - a first EuroPay-MasterCard-Visa chip (212,312) having a secure memory storing a pre-stored private key; - a first microprocessor; and - a first application; and - a mobile device (130,402) that includes: - a second secure memory; and - a second microprocessor; characterized by - a backend system storing a public key; - wherein the first application, when executed: - transmits, via a Bluetooth or Bluetooth Low Energy network (110,404), a connection attempt to the mobile device (130,402); - receives, via the Bluetooth or BLE network (110,404), an encrypted handshake from the mobile device (130,402), wherein the mobile device (130,402) encrypted the handshake using the downloaded public key, preferably the encrypted handshake comprises a static string of random length and random digits; - decrypts, using the private key and microprocessor, the encrypted handshake and validates the handshake; and - creates, in response to validating the handshake, a Bluetooth or BLE connection between the dynamic transaction card (120,...) and the mobile device (130,402); - wherein the mobile device (130,402) is configured to receive login credentials from a mobile device user and to transmit the login credentials to the backend system; and - wherein the backend system is configured to receive login credentials, and upon validation of the login credentials, to transmit the public key to the mobile device (130,402). - a dynamic transaction card (120,200,300) that includes: - a first EuroPay-MasterCard-Visa chip (212,312) having a secure memory storing a pre-stored private key; - a first microprocessor; and - a first application; and - a first EuroPay-MasterCard-Visa chip (212,312) having a secure memory storing a pre-stored private key; - a first microprocessor; and - a first application; and - a mobile device (130,402) that includes: - a second secure memory; and - a second microprocessor; characterized by - a second secure memory; and - a second microprocessor; characterized by - a backend system storing a public key; - wherein the first application, when executed: - transmits, via a Bluetooth or Bluetooth Low Energy network (110,404), a connection attempt to the mobile device (130,402); - receives, via the Bluetooth or BLE network (110,404), an encrypted handshake from the mobile device (130,402), wherein the mobile device (130,402) encrypted the handshake using the downloaded public key, preferably the encrypted handshake comprises a static string of random length and random digits; - decrypts, using the private key and microprocessor, the encrypted handshake and validates the handshake; and - creates, in response to validating the handshake, a Bluetooth or BLE connection between the dynamic transaction card (120,...) and the mobile device (130,402); - transmits, via a Bluetooth or Bluetooth Low Energy network (110,404), a connection attempt to the mobile device (130,402); - receives, via the Bluetooth or BLE network (110,404), an encrypted handshake from the mobile device (130,402), wherein the mobile device (130,402) encrypted the handshake using the downloaded public key, preferably the encrypted handshake comprises a static string of random length and random digits; - decrypts, using the private key and microprocessor, the encrypted handshake and validates the handshake; and - creates, in response to validating the handshake, a Bluetooth or BLE connection between the dynamic transaction card (120,...) and the mobile device (130,402); - wherein the mobile device (130,402) is configured to receive login credentials from a mobile device user and to transmit the login credentials to the backend system; and - wherein the backend system is configured to receive login credentials, and upon validation of the login credentials, to transmit the public key to the mobile device (130,402).