Abstract
Designing effective and efficient user interfaces for supporting complex tasks on mobile devices remains an intriguing problem. The rapidly evolving hardware and software mobile environments are complicating the design of elaborated applications like travel planning. Allowing mobile users to review their travel-plan information while travelling has been addressed by a recent R&D project. In order to improve usability and derive good design guidelines, two alternative WAP-based solutions were experimented: one based on providing explicit guidance and information, and another focussed on brevity and iconic metaphors. These two designs enabled to investigate mobile users’ preferences and behaviour and the effects on usability and effectiveness. A user study was conducted and users’ behaviour on both variants was logged. Using objective measures and users’ subjective perceptions, the effects of design options, users’ age and proficiency with WAP applications were tested. This study allowed deriving some guidelines by analysing which graphical components better support mobile usability, and which solutions should be avoided.