This paper describes the process and outcomes of the evaluation of a user interface prototype running on a Personal Digital Assistant (PDA). The prototype was developed in the context of the IST-funded project WARD-INHAND and implements a PDA version of a ward information system. The evaluation, carried out by the IS4ALL project, was based on a usage scenario comprising mock-ups and textual descriptions of the typical tasks of the system. Although the evaluation revealed a range of usability issues to be addressed, in this paper we consider only those which feature prominent in the vast majority of PDA-based applications, such as adaptability, individualisation, user profiling, alternative dialogue styles, localisation, etc., and propose design solutions of general purpose, as a basis for improved design practice.