On the phones that have a home button and 3d touch, you can switch to the previous app or bring up the app switcher with a force touch swipe from the left edge, fyi.
I had forgotten about that! While this is true, I find it a lot more difficult than the new mechanic since it's a lot slower.
> (not sure what the name is, previously you would double tap the home button).
The SpringBoard?
[1] Yes, this is my opinion and not everyone might agree with me.