Web applications, often referred to as AJAX, are increasing in number and capabilities. Application developers now routinely target the Web instead of operating systems. A core set of Web Standards—HTML, CSS, JavaScript and DOM—form the foundation for most Web applications.

One guiding principle of the Web is that there is only one Web; the same Web standards and the same Web content should be usable on all Web devices. As such, Web applications are challenging for mobile devices. For example, they often demand certain screen sizes.

This paper will present the state of the art in Web Applications. Existing and emerging technologies will be discussed, and special emphasis will be put on mobile Web applications.