Pencil Project is an open-source GUI prototyping tool. Developed by Evolus
License: Open Source
Pencil Project is a free, open-source tool ideal for creating UI mockups and wireframes with its user-friendly interface and wide variety of templates. In contrast, Edraw Max offers a more comprehensive set of diagramming tools, catering to a broader range of professional diagramming needs, but comes with a higher cost and a steeper learning curve.