Abstract: A method of operating a retail check-out station. A customer selects items to be purchased, and scans bar codes attached to the items, using a cell phone camera. The bar codes identify the items. The cell phone extracts data from multiple bar codes and assembles the data into a different type of code, such as a 2-D bar code. The cell phone prints out the 2-D bar code, either on paper or on its display. The check-out station scans the 2-D bar code to obtain the identities of the items, and completes the transaction.