Animating elements of views that are being transitioned to

Question

I have a question regarding the transition in this gif:

It's a beautiful app called Dark Sky.

How does one start animating things in the upcoming view on the transition?

Is this multiple views animating in one view controller, or multiple view controllers animating in and out?

Here as we scroll to the next view, we see the elements are appearing independent from each other and moving independently from each other as well.

Answer 1

Try taking a look at Apple's WWDC 2013 video for session 217. They do something similar with the lock screen on an iPhone.

Specifically, it appears that the Dark Sky app uses nested UIScrollViews. Each of those "rows" is itself a ScrollView inside a paging ScrollView. When the overall "page" of the outer ScrollView is dragged, they will programmatically wait for a certain point in the scroll for each of those rows to "catch" and then follow along with the outer scroll view.