Maqetta - Maqetta is an open source project that provides WYSIWYG visual authoring of HTML5 user interfaces.
VisualNEO Web - Visually design and develop Web Apps.
PageBreeze HTML Editor - A full-featured but easy to use visual (WYSIWYG) HTML editor for creating web pages. Includes a completely new editor with support for the latest HTML standards, many new formatting features, improved stability and ease of use.
Openbexi - OpenBEXI is an open and free source, WYSIWYG editor compatible with Windows, Mac, and Linux with a browser-based interface.
NSB/AppStudio - NS Basic/App Studio is a complete, powerful development environment.
Amaya - Amaya is a web editor that is used for creating and updating the documents directly on the websites.