A method of interacting with a product item. The product item comprises a product contained in a package, the package having an interface surface containing information relating to the product, the interface surface having disposed thereon coded data identifying a product identity and a plurality of locations on the interface surface. The method comprises the step of: (a) sensing at least some of the coded data in the vicinity of the sensing device when a user interacts with the product item by placing a sensing device in an operative position relative to the interface surface; (b) generating indicating data using at least some of the sensed coded data, the indicating data comprising data regarding the identity of the product item and a position of the sensing device relative to the interface surface; and (c) sending the indicating data to a computer system. The method enables the computer system to identify the interaction between the user and the product item.