Drawing ap I don't need to record, or draw on stored video files, or anything fancy--I just want to be able to draw lines onto the live camera view. For instance, I'd trace a shape in the world, then carry what I've drawn over to another shape to do a quick comparison. (So drawing on a static photo isn't enough.) Any recommendations? iPad preferred, iPhone OK too. Thanks!
Sounds like you need Doodley Moore, free too: https://itunes.apple.com/gb/app/doodley-moore/id495619963?mt=8
Perfect! Thanks! I never would have found that. It's even Universal and a small download. I'm going to try to use it in teaching juggling. Draw guides for different throws and let people try to follow the lines. Just an experiment.