Existing complex and difficult picture apps. So when I found an easy app, there were a lot of apps that had no basic functions and couldn't decide the color. I thought about my drawing board! "What should I do with the existing drawings so that users can do it comfortably?"" I only added key functions. If you want to make a mistake or draw again? It's a function of rewinding and initializing. What color do you want? Designating the background color and pen color will make it easier. If you