This is getting a bit confusing. Not every app on the Start Screen opens on my Desktop, very few in fact. What I meant was when I click on e.g. Internet Explorer on the Start Screen it opens up full screen. It's true I also have Internet Explorer on my Desktop as well, which I open from the Taskbar. I guess Brink I should have said 'full screen' rather than on the Start Screen. I realise on Windows 10 all the apps on the Start Screen open on the Desktop, but not on W8. I've just worded it all wrong!!
Edit: I guess I mean the modern Metro UI screen versus the Desktop screen.