A handheld display device for imaging and displaying a printed substrate containing a printed hyperlink. The device comprises: an optical sensor for imaging an area of the printed substrate and generating image data; a processor for determining interaction data using the image data, the interaction data identifying a substrate identity; a transceiver for retrieving display data corresponding to the printed substrate using the substrate identity; and a touch-sensitive display screen for displaying display information based on the display data. The display information comprises a displayed hyperlink corresponding to the printed hyperlink on the substrate. The device is configured such that user interaction with the displayed hyperlink via the touch-sensitive display screen causes retrieval and display of hyperlinked information on the screen.