Influence of mental model of GUI on usability

Applications operated on smartphones and other devices with a small user interface area on the screen and a large number of functions and contents will inevitably increase the number of operation procedures and make them more complicated. However, compared to the attention paid to information architecture and interaction in realizing intuitive user interfaces, less attention is paid to icons, and there are many examples where generic icons are used. Therefore, when icons and the functions they represent are different for each application, or when icons are unintelligible because of the distance between the user's mental model and the icons, the cognitive burden on the user is amplified, which may affect usability. We compared the usability of icons, one of the GUI elements, by focusing on their metaphors, and showed that the selection of metaphors that are in line with users' mental models has a positive effect on usability by improving the performance of task completion time and the number of errors. This study clarified the influence of the degree of congruence between the metaphor used and the user's mental model on the usability of icons, one of the GUI elements.