Love the app. I use it to teach computer science and mathematics subjects to college students in online mode. For the math course, at present I start with an empty white background and write on it. I was wondering if it would be possible, using your app, to recreate the experience of teaching on a blackboard by simulating the sound that the chalk makes on the blackboard, so that when I write on a black background template (with white color pen), if I enabled this option, then the students will hear a sound whenever my apple pencil is writing on the surface. That would be cool!