This application was designed to be a quick and easy way to annotate PDF files, and you can do so in a variety of ways.

It supports a wide variety of tools, including a pen and pencil, eraser, and color pencil. You can even use your finger to draw, as long as it's not a finger that contains a stylus.

It also supports a wide variety of different colors.

You can add text to your annotations, as well as make them much more complicated.

You can also draw on top of PDFs, which can be extremely useful, especially for more complex PDFs.