Gimp is a free software which enables advanced features in painting, just like Photoshop does. The best feature is that it is free, this is quite obvious. The program features a lot of stuff and is compatible with all operating systems. The program has a lot of gradients, uses layers and much more.
Trying this program, was a bit more difficult than Photoshop, but this might be because I have never used it and have years practicing with Photoshop. You can even create geometric objects, just like Illustrator.
You can download the program by clicking here.
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