The present invention enables users to instantly purchase desired items with their mobile device (e.g., cell phone/PDA) while viewing services such as the Home Shopping Network, QVC, etc. on television or the Internet (using a PC). When the service displays a product on-screen, a barcode would also be displayed associated with the product being sold. To purchase the item, the user utilizes a camera-equipped mobile device to scan the on-screen barcode. The barcode information and user information is then sent to the vendor's server where it is processed. The preexisting transaction system is used to complete the user's transaction. Once the transaction has been complete, the vendor's server sends a confirmation message to the mobile device.