A hand-held modular printer system for printing a stored image, the printer system comprising a memory module in which the image can be stored; a printer module adapted to be releasably interconnected with the memory module, the printer module including an elongate body defining a transverse print media passage and a printer which is arranged within the body so that the stored image can be printed onto print media which passes through the passage, the printer module further including a print media feed arrangement located within the body, the print media feed arrangement comprising a plurality of rollers configured to feed the print media through the passage and a motor arrangement for driving at least one of the rollers; and a pen module adapted to be releasably interconnected with the printer module and which includes a nib which can dispense ink. The printer module is housed in a substantially cylindrical housing, and the hand-held modular printer system further comprises an ink cartridge, the ink cartridge substantially extending the length of the printer module and shaped such that a major surface of the ink cartridge has a curvature substantially matching that of an internal surface of the cylindrical housing, whereby the ink cartridge is nestled against the cylindrical housing.