Oracle Accessibility Program - General information about accessibility at Oracle. Click Database Products or Open all and locate the relevant version of APEX.
Plug-ins - Plug-ins enable developers to readily extended with custom item types, region types, processes, and dynamic actions. Once defined, plug-in based components are created and maintained very much like standard APEX components.
Universal Theme Sample App - Sample app hosted on apex.oracle.com with information about Universal Theme, including a Migration Guide to move from older themes.