Digital Painting and Drawing
Autodesk SketchBook Copic Edition - This is the limited edition of SketchBook Pro with 72 Copic colours to choose from
Krita - Krita offers CMYK support, HDR painting, perspective grids, dockers, filters, painting assistants, and many other great features
GIMP - GIMP is a well known free alternative to Photoshop with similar features
Mischief Free Version - With six essential brushes, a basic palette of colors and an infinite vector canvas, Mischief-Free is perfect for hashing out ideas, life drawing, and endless doodles
Digital Painting and Drawing
Autodesk SketchBook Copic Edition - This is the limited edition of SketchBook Pro with 72 Copic colours to choose from
Krita - Krita offers CMYK support, HDR painting, perspective grids, dockers, filters, painting assistants, and many other great features
GIMP - GIMP is a well known free alternative to Photoshop with similar features
Mischief Free Version - With six essential brushes, a basic palette of colors and an infinite vector canvas, Mischief-Free is perfect for hashing out ideas, life drawing, and endless doodles
MyPaint - MyPaint is a fast and easy open-source graphics application for digital painters, and comes with 39 different brushes
Verve Painter - Verve is a small painting application that uses fluid dynamics and brushes to push the paint around, though it is still in development.
Inkscape - Inkscape is an open-source professional quality vector graphics software with sophisticated drawing tools with capabilities comparable to Adobe Illustrator.
FireAlpaca - A similar program to Paint Tool Sai that offers features such as a snap feature which creates a variety of perspective overlays.
MediBang Paint - A free lightweight painting program for Windows, Mac Os and Android with cloud saving to allow users to easily switch between platforms.
SpeedyPainter - Basic painting program with a simple layout and features such as perspective grids and reference view mode
3D Modelling
Google Sketchup - Drawing-based tool for architects, designers, builders, makers and engineers who design for the physical world. SketchUp Make is a free version and SketchUp Pro is a paid version with additional functionality.
Sculptris - A free, introductory digital sculpting tool, a great stepping stone for digital sculptors, created by the makers of Zbrush.
Blender - A powerful application with full-fledged professional tools, Blender has a wide community and resources to help you learn.
SculptGL - This handy modelling program works online in your browser and is compatible with wacom tablets
Animation
Synfig - Synfig Studio is a free and open-source 2D animation software, designed as powerful industrial-strength solution for creating film-quality animation using a vector and bitmap artwork.
EmoFuri - EmoFuri is a new animation software that helps artists easily animate photoshop illustrations in a 2D-3D style.It uses PSD files of character illustrations to animate them.
Pencil2D - Pencil2D is an open-source animation/drawing software that lets you create traditional hand-drawn animation using both bitmap and vector graphics.
Live2D - This increasingly popular 2D-3D animation software is similar to Emofuri with sample models available to experiment with, and is also available in english.
Pixel Art
Piskel - An online pixel art app that lets you animate pixel art with a live preview of your work.
Piq - While it doesn’t have the best looking layout, this online tool has lots of interesting features including a colour-drift tool that’s great for making colour palettes.
Etc
Thisissand - An online fun and unique playground for creating colourful sandscapes, also comes in an app version
Flame Painter - A free demo of the full program, it allows you to try out the flame generator and change different brush settings and paint your own flame paintings
Silk - An online interactive generative art program that creates bright silk-like patterns, with options to change colours and rotational symmetry.
Bomomo - This interesting program has a group of dots that move around the screen in the pattern you choose, then paint the canvas according to when you click the screen.
Drawpile - Drawpile is a software collaborative drawing program that allows multiple users to sketch on the same canvas simultaneously.
Sources: Drawingden
Bonus
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