Abstract
Educational applications provide engaging learning experiences particularly for children, but their visual nature limits their usefulness and accessibility for the visually impaired (VI). By utilizing physical objects in the interactions, tangible user interfaces (TUIs) could make educational applications more accessible for VI children. Fully understanding the specific needs of users and involving them in the system design and testing are necessary for developing usability and accessibility guidelines to improve the overall user experience for such applications. This paper reports on the user-centered design process for an innovative, engaging TUI-based educational application for VI children, wherein several gamification elements were included to enhance the user experience and increase engagement. An evaluation was also conducted over two iterations to assess the TUI application's usability quantitatively and qualitatively. The results of the evaluation sessions generated several design recommendations and guidelines to enhance educational TUI-based applications for VI children.