Pencil - Pencil is a free in addition to open-source GUI prototyping application that may be quick, easy in addition to works across multiple programs. Pencil provides various pre-installed shapes collection for pulling different types of graphical user interface ranging from desktop to be able to mobile platforms. Starting coming from 2. 0. 2, Pencil is shipped with Android os and iOS UI stencils pre-installed. This makes that much easier to start protyping apps using a simple unit installation. The list of pre-installed collections also includes general-purpose shapes, flowchart elements, desktop/web UI shapes, Android in addition to iOS GUI shapes. You can also get many other collections developed by the city which will be freely available on typically the Internet. Pencil also helps any exports formats which include PNG and HTML. Any time exporting to HTML an individual can even define back links and behaviours, allowing an individual to 'walk' clients by means of the UI mockup together with buttons which actually job! This makes it significantly easier to model to be able to flow of an graphical user interface. Pencil also supports conveying documents into popular platforms including OpenOffice/LibreOffice text paperwork, Inkscape SVG and Flagstone PDF.