I was frustrated with drawing apps where the eraser was E and the pen was P. Often, when I'm drawing, I want to quickly erase and then switch back to the pen. As one of my hands is on my mouse or tablet, I have to use my other hand to reach across the keyboard. I wanted a drawing app with customizable keybindings, so I made qboard a while back and have used it since.I talk more about the design principles on the Github repo: <https://github.com/cjquines/qboard/#design-principles>.