A free app for Android, by Kris Pixton.
PathPix is a free drawing game that allows you to draw and paint bright, bold lines connecting two numbers. The path must be long enough to reach the end point, and it must match the number on both ends. There is only one way to do it, and all the squares will contain a piece of the path when the puzzle is solved.
You get a little extra help when you finish the puzzle. You will get a little clue about what the picture is about, and you can see a preview of the finished puzzle in the app.
If you are a beginner, PathPix is a good way to learn how to draw. If you are an artist or want to do a painting, this is a fun way to practice your drawing skills.