Cross platform consistency and cognitive compatibility: the importance of users’ mental model for the interaction with mobile devices

This paper focuses on the impact of users’ mental model for the performance when interacting with mobile devices. Investigating the interrelation between the quality of the mental model and the performance, users had to accomplish standard applications with cell phones (study 1) and a PDA (study 2). Navigation routes were individually analyzed and the respective effectiveness and efficiency of menu navigation was determined. After task completion, users were requested to visualize their mental representation of the device’ inherent structure. To learn the usability demands of a broad user group, younger and older adults were examined. The outcomes clearly demonstrated the importance of a correct mental model for the navigation performance. Users who had formed the correct mental representation of the respective device structure were extremely advantaged compared to users who did not have an adequate representation. In addition, it was found that the ageing disadvantage can be diminished by the correct mental model.