A moire pattern is an interference pattern created, for example, when two grids are overlaid at an angle, or when they have slightly different mesh sizes. You can change color, number, thick, slope of lines and type of line.
Love the idea. Would like to see generalized equation with adjustable parameters. Cannot scroll down or rotate settings screen. 10/6/2018 -- Thx. I can scroll the settings menu now. I increased the rating to 4 stars. Rotating the screen is not very important to me. I am wondering if you could let people draw their own pattern and then your program could make it "Moire ready".