I'm curious how iOS 7 mail app is moving and dismissing the keyboard according to user's touch drag on new message screen.
Also it's implemented on comments screen of instagram app.
Can it be implemented through public apis?
UIScrollView
has a property called keyboardDismissMode
that allows you to set different behaviours. I think this is what you want:
scrollview.keyboardDismissMode = UIScrollViewKeyboardDismissModeInteractive;