Pencil2D

Pencil2D is a completely free and open source drawing app released under the GNU General Public License with Qt framework. With it, you can create traditional animations from an easy-to-use interface. The original version of the program, simply called Pencil, was abandoned and discontinued in 2009 by its original creators. This led to the creation of several forks, one of which was Pencil2D, which became the new standard.

The aim of Pencil2D is to help you create cartoon animations using traditional methods, such as onion skinning and other popular techniques. To do so, the program lets you work with a complex system of five layers, with which you can manage all the drawings you create or import to your canvas, as well as the rest of the files you plan to work with. At the bottom of the screen, you'll find the classic timeline, from which you can easily manage the duration and position of each part of the animation, modifying any parameter just by dragging and dropping.

One of the strengths of Pencil2D is that, although you can save all your projects in the program's native format to continue working on them later, you can also export them in a snap. On the one hand, you can export any project as a sequence of images in PNG, BMP, JPG, or TIFF. On the other hand, if you prefer, you can export your projects as video files in AVI, MP4, APNG, or WebM formats. In this way, no matter the demands of your work, you'll always be able to do what you need without running into any problems.

Pencil2D is an excellent traditional drawing app that makes creating simple animations a breeze. Another aspect to take into account is that, on the program's official website, you'll also find tons of video tutorials made to teach you how to create all kinds of advanced effects.