Gate5 is a technology company specialising in location-based applications for mobile terminals and the Internet. For the web-based part of Gate5's product family, preview developed an interface concept that allows the configurations to be tailored exactly to the respective product. The interface design styleguide documents the modular principle of interface design. The design guidelines that form the basis of the Gate5 product family can be used for development of interface design, as well as for expansion and modification of the location-based systems.