I use an app called Concepts for taking notes during games and drawing maps freehand. The infinite canvas is awesome. I have heard really good things about Goodnotes, but it is only available for Apple in a stable release (it’s in beta for Windows).
I have also been using Tana lately, which is pretty much the exact opposite. It has a somewhat steep learning curve but it is really powerful and it is so satisfying when you figure out how to use their tools to solve your specific issue. If you can figure out grappling in Pathfinder, you can figure out Tana.
No worries bud. Thanks for all your work.