Abstract: Systems and methods are provided for providing a more seamless purchasing experience using a mobile device. The mobile device acquires data, such a barcode image, an image of an object or text, or audio data. A non-limiting example of a barcode is a Quick Response (QR) barcode. The acquired data is then used to obtain a network address of a payment website or webpage, which allows a user to make a purchase for a given product or service. The mobile device then launches the payment website or webpage. A user can enter into the mobile device, through the payment website or webpage, a supplemental ID used for authenticating the transaction.

Abstract: A user may claim to have not made or allowed a transaction and that the transaction was made in error. Where it appears the user has not authorized the transaction, the funds of the transaction are returned to the user, or are charged back. Systems and methods provide a way to confirm whether or not a transaction was actually authorized by the user, thereby settling a chargeback dispute for a previously executed transaction. The method comprises receiving the dispute regarding the transaction including associated transaction data, and retrieving a digital signature associated with the transaction data, the digital signature computed by signing the transaction data. The digital signature is then verified using a public key, wherein the public key corresponds to a private key stored on a mobile device. It is then determined whether or not the transaction is fraudulent based on a verification result of the digital signature.