Dude. Stop and think for a moment. If I am able to render anything on the screen at all, it means I’m the foreground app on iOS. I don’t need to fake being a keyboard, because I can use the real thing Apple provides. So no, I’m not saying it’s impossible if I can render anything at all, what I’m saying is that outside being the foreground app, rendering anything on screen is impossible outside very tightly controlled interfaces (like custom keyboards that this thread was about before you side tracked it).

I am only talking about what the app does when it is the foreground app. I should have addressed that in the previous comment.

It's not a sidetrack, because that's what the actual article is about.

So if you really were talking about the foreground app and not just covering now, then why does one need to make a fake keyboard!? That makes no sense at all.

I was just making a more fundamental point (see my middle para) and decided to hang it off this thread rather than making it top level.

I didn't have a specific scenario in mind.

But to address your question ...

Say a user is reassured because he knows that only approved keyboard apps can accept passwords.

This malware app pops up a password prompt AND some images and input buttons that looks very much like a 'proper' keyboard.

The user enters his password.

Game over.