Usability evaluation of mobile passenger information systems

Public transportation becomes increasingly diverse because of innovation in transport modalities and a large number of service providers. For facilitating passengers' comfort, intermodal passenger information systems are required, which combine data of different providers and transport modes. Therefore, context sensitive mobile applications are promising solutions to supporting passengers at every stage of their trip. Crucial for the success of these applications is their usability. In this paper, a prototype of an intermodal passenger information system is investigated in a usability evaluation and tested in comparison to the leading mobility application in Germany. Both iOS apps were evaluated with a questionnaire using the system usability scale (SUS) in a lab setting (n=20) and in a field test (n=20). Additionally, participants of the field test were interviewed retrospectively about app and setting. The user feedback was beneficial in learning about users' expectations towards information retrieval procedure in and functionalities of a passenger information system. The usability evaluation basically revealed easy to improve usability problems, but also a trust issue and the need for a participatory component in public transportation, probably by integrating social media.