TRANSLATING USER INTERACTION WITH A TOUCH SCREEN INTO INPUT COMMANDS

Systems and techniques for translating user interaction with a touch screen into input commands. In one aspect, a touch screen system includes a touch screen graphical display, a command interpreter configured to identify modifier interactions with the graphical display and, in response to identification of the modifier interaction, modify the interpretation of other interaction with the graphical display, one or more persistent data storage devices. The data storage devices store a first set of rules for interpreting user interaction with the graphical display and a second set of rules for interpreting user interaction with the graphical display. The first set of rules interpret motion across a map or a proper subset of a collection of information as a scrolling or panning command. The second set of rules interpret the motion as a glyph. The command interpreter is configured to modify the interpretation of the other interaction by switching between interpretation under the first set of rules and interpretation under the second set of rules.