Pencil is built for the purpose of providing a free and open-source GUI prototyping tool that people can easily install and use to create mockups on popular desktop platforms.
Easy GUI Prototyping
Pencil provides various built-in shapes collection for drawing different types of user interface ranging from desktop to mobile platforms. Starting from 2.0.2, Pencil is shipped with Android and iOS UI stencils pre-installed. This makes it even easier to start protyping apps with a simple installation.
Popular drawing features are also implemented in Pencil to simplify the drawing operations.
Built-in Shape Collections
Starting from 2.0.2 Pencil has even more shape collections included by default. The list of built-in collections now includes general-purpose shapes, flowchart elements, desktop/web UI shapes, Android and iOS GUI shapes.
There are also many other collections created by the community and are distributed freely on the Internet. You can easily grab a collection and install it into Pencil with a simple drag-and-drop operation.
Exporting to Different Output Formats
Pencil supports outputting the drawing document into different types of formats. You can have your drawing exported as a set of rasterized PNG files or as a web page that can be delivered to the viewers.
Pencil also supports exporting documents into popular formats including OpenOffice/LibreOffice text documents, Inkscape SVG and Adobe PDF.
Easily Find Cliparts from the Internet
Pencil has a clipart browser tool that integrates with OpenClipart.org to let users easily find cliparts by keywords and added them into the drawing by a simple drag-and-drop operation.
Clipart listed by the tool are in vector format and hence good for users in scaling to appropriate sizes.
Inter-page linking
Elements in a drawing can be linked to a specific page in the same document. This helps user define the UI flow when creating application or website mockups.
Linking’s defined in a document are converted into HTML hyper-links when the document is exported into web format. This process creates an interactive version of the mockup in which viewers can see a simulated flow when clicking on the UI elements.
