Since the birth of the first GUI, adaptive user interfaces have been used to cover a wider range of possibilities seeking alternatives for the presentation of the information. Starting with small personalization features, more related to practical interaction, first customizable menus and graphical elements arose. Subsequently, the possibility of breaking down the interaction barriers has grown. From the user perspective, these limitations are usually caused by physiological disabilities, which imped users to properly interact with or consume information.
With the arrival of mobile telephony and portable devices, a wider range of possibilities regarding adaptive user interfaces have emerged. This market evolves continuously,bringing smaller, more powerful and wearable devices. This trend has strengthened the adaptive user interfaces within this market. Nevertheless, the user interface adaptation for these devices is far from the advances in static devices, which are able to perform complexer computations. Besides, more problems are added to the equation if the context is considered. The context situation, characterized by the set of singular features which define it and their quality might make the context dynamic. Thus, in each case, different adaptations or configurations might be needed. In fact, users may suffer from specific and/or temporary disabilities due to the context situation. This issue brings new challenges to adaptive user interfaces systems. Hence, from these challenges new adaptive tools started to be included and integrated with the purpose of minimising the identified interaction barriers. This also aimed to allow users to feature a sufficient interaction experience.
In this dissertation these problems are faced, aiming to reduce the boundaries between the user and the device in several limiting situations. To solve them, a dynamic and mobile user adaptation system is presented, principally supported by a semantic model which includes a conceptualization of the user, the current context and the device. Its design allows increasing the expressiveness of the user interaction contextual and interaction needs, also taking into account the features provided by the user's device.