How to Exit from an app

Have there a solution to do Exit in app?

I’ve use handler UrlChanged in WebView to decide when users came to Start-page after pressing Back-Button, and when got url “about:blank” I need to close app.

I’ve try to use module “bolav/fuse-homescreen”, but it not working, didnt compile in latest version (log says that HomeScreen already defined in that file, but its once only…).