Barriers of Information Access in Small Screen Device Applications: The Relevance of User Characteristics for a Transgenerational Design

The proliferation of ubiquitous computing is accompanied by the development of devices, which promise to facilitate the daily living activities of people. However, the question if mobile devices address the usability demands of older users is still unsettled. This paper reports the findings of a series of studies that examined the performance of younger and older adults when using personal data management software applications of a PDA. In order to learn about the ageing impact, the influence of user characteristics like spatial and memory abilities, the subjective technical confidence and computer-expertise on performance outcomes were analysed. Beyond quantitative performance measurements, the major shortcomings in interface design were identified. Results showed that older users reached lower performance outcomes. Even young adults did not reach a perfect performance level, hinting again at shortcomings in the design of PDA applications. Overall, the findings demonstrate the need to include user characteristics in interface design.