Developer's DescriptionBy EvolusDesign diagrams and make GUI prototyping on your Firefox browser.Pencil for Firefox is a diagramming add-on for Mozilla Firefox which can perform GUI prototyping and simple sketching. It includes rich features like built-in stencils for diagraming and prototyping, multi-page document with background page, inter-page linkings, on-screen text editing with rich-text supports, exporting to HTML, PNG, Openoffice.org document, Word document and PDF, undo/redo supports, and installing user-defined stencils and templates.