Unfortunalty, the only reason I was able to make this work in a day is that it uses two proprietary Apple libraries.

PencilKit — which provides all of the UI for drawing and selecting drawing tools.

ReplayKit - which is designed for games but, I'm using it to just record the whole screen.

There is really not that much code outside of just calling into those frameworks which is what allowed me to make this in such a short time. If these types of libraries exist on Android, I could probably create something, but I'm not super familiar with Android's library ecosystem.