Tap to focus on camera apps, Supposedly not possible, but a bug in my app enables it (although useless)

Question

Hello

I would like to get tap to focus in my app and the controls are hidden

Supposedly this is impossible but I know its not. I have a simple iAD dragged into an overlay, no code or anything. When I click on the iAD nothing. but when I close it with the home button I get a modal exit of the nonexistant iAD and the camera apps relaunches but in the top left with only a small portion viewable. But this time the tap to focus is enabled.

So how can I do this without the bug?

Thanks!