It's 2017 and a lot of info on this is pretty dated. I've heard TeamViewer can, then it seems like it can only control your app.
Anyway I got my parents an iPad for Xmas. They know nothing about computers. I need something I can use to remote in and help them (preferably free). If I have to set up a vpn and host some kind of software it's not a big deal. Since they don't have a computer I can not use QuickTime. It has to be one click easy for them.