Homebrew Homebrew app Need help building custom parental control brew app

[Guisardo]

Hi all!
I'm on the path of building a parental control app. Something simple to start.

An admin screen where you could set a schedule with the allowed times and a key combo setup to unlock and/or extend the allowed time; a lock screen to somehow prevent or annoy the user gameplay when the allowed time runs out; and an internal scheduler that runs in background and, using the times configured through the admin screen, launches the lock screen when needed.
I have some progress but I'm hitting a dead end so I will need suggestions.

• As I understand, background task can't access the screen, so the scheduler won't be able to simply show the locker. Is there a way to launch a separated .nro app from a background process? If that is possible, I could simply move the lock screen to a separated app, but if that is not possible I'll need some suggestions.
• Is there a way to automatically run a brew app at the start of the CFW? I will need the background scheduler to run automatically after every restart. The user timers don't execute if the app is not running, right?

I'm starting to check libtesla as an overlay framework to try to overcome those dead ends. Is this the right way to go? Is there any simpler mechanism to run something at background that automatically starts and could interrupt the gaming?
Thanks in advance!