Duarte, CarlosCarriço, LuísCarriço, Luís and Correia, Nuno and Antunes, Pedro and Jorge, Joaquim2021-11-022021-11-022021978-3-03868-166-3https://doi.org/10.2312/pt.20041491https://diglib.eg.org:443/handle/10.2312/pt20041491ln this paper we present the results of a set of usability evaluation studies on Digital Talking Books. Digital Talking Books aim to provide better access to literary content for the blind and visually impaired. Departing from their digital base, we developed enriched books, targeting broader audiences and usage situations. The books can be enriched with different media content, like images and sounds, supporting multimodal interaction and multimedia presentation. Enlarging the number of interaction possibilities, while making the books more attractive, also increases the possibility of usability problems. This is why it is so important to perform usability evaluation of the generated interfaces. A special focus of the evaluation was given to the synchronization related issues. Synchronization flaws detected by the users were the cause of discomfort and loss of concentration. Alternative synchronization visual marking was employed to circumvent these problems. Tests also provided insight on what modalities are favoured by the users for specific interaction tasks, and confirmed the importance of the availability of multimodal interaction.UsabilityEvaluationMultimodal interfacesDigital talking books10.2312/pt.200414919-17