As mobile handheld devices are being used increasingly for Web access, ease of use has become an important issue for users. However, the unique physical features and inherent constraints of handheld devices and wireless networks present a number of critical challenges for both taking advantage of the convenience of mobile devices and enabling efficient Web access. In addition, users have different information needs and preferences. They want to receive content that is customized to fit their information needs and desires. Therefore, adapting the original Web content dynamically to cope with the constraints of mobile handheld devices, the nature of wireless networks, and user preferences becomes very important. Although there have been some preliminary studies on the adaptation of Web content for mobile devices, research in this field is still at its early stage. There is both a lack of theoretical frameworks and guidance for building adaptive Web applications as well as empirical evidence to demonstrate the effectiveness of content adaptation on Web access through mobile handheld devices. In order to meet this challenge, this dissertation presents an innovative theoretical framework, based on the literature review and related theories, for developing adaptive mobile Web applications. The framework consists of three major adaptation processes: content selection, content customization, and presentation adaptation. Content selection refers to filtering irrelevant content and delivering only what is interesting to users. Content customization is the tailoring of content to fit the characteristics of mobile handheld devices and wireless networks. Presentation adaptation involves generating effective Web content presentation for easy Web browsing and searching. These adaptation processes utilize information from various sources to generate adaptive content and presentation in real time, based on the preferences of users, the features of mobile handheld devices, the wireless network status, and the contextual environments. A prototype system called M-Web has been implemented based on the proposed framework. It uses a novel hybrid approach to presentation adaptation, which integrates three presentation adaptation techniques, namely tree-view adaptation, hierarchical summarization, and personalized visual search. Another major contribution of this dissertation research is to empirically examine the effect of presentation adaptation on mobile Web browsing. A carefully designed and controlled laboratory study involving 60 participants was conducted to evaluate the effect of three presentation adaptation techniques on users' information searching/browsing performance and users' perception of mobile Web browsing. The results indicated that presentation adaptation had a significant positive impact on users' performance and perception of Web browsing and information searching. When compared to the system without presentation adaptation, the M-Web system reduced users' searching time, increased users' searching accuracy, and improved users' perception of accessing the Web via mobile handheld devices
