Mobile touch-screen devices are becoming increasingly more popular across a diverse range of users. Whilst these smart phone devices offer users access to a wealth of information and utilities via their downloadable apps, there are still a large proportion of users who are unable to fully interact with the technology due to additional interaction needs. In this paper we present an evaluation on the use of shared user modeling (SUM) and adaptive interfaces to improve the accessibility of mobile touchscreen technologies. Our studies involved 12 participants with various visual and mobility impairments.