Pingendo : The simplest app for Bootstrap prototyping. Create quality HTML prototypes quickly, using popular open source tools like Bootstrap, LESS, Fontawesome ...
Inkscape : Inkscape is a professional vector graphics editor for Windows, Mac OS X and Linux. It's free and open source.
ClickHeat : ClickHeat is a visual heatmap of clicks on a HTML page, showing hot and cold click zones. ClickHeat is an OpenSource software, released under GPL lice...
Modelio : Modelio is an open source modeling environment (UML2, BPMN2, ...). Based on a 20-year track record of high end commercial products, Modelio delivers a...
Wireframing, mockups and prototyping for websites and applications
