What is this?

[oldcelt]

Why does the content of the iPhone screen move down leaving a space at the top of the screen when I tap the home button lightly twice?

 

[Zexel]

That's called Reachability. It's a feature on the iPhone 6 and iPhone 6 Plus that allows you to easily get to the top half of the screen without having to use two hands.

 

[oldcelt]

Thanks!#

 

[LxHunter]

Yes reachability.
Wish it just shrunk whole screen to bottom left or right.
I have 6+ and one big screen.
Starting to learn how to use it.