The iOS 9 SDK adds a new API for easier layout of views called UISTackView. UISTackView makes it easy to stack a collection of views horizontally or vertically with a number of different alignment options.
Here’s an open source library from Omar Abdelhafith called OAStackView with the goal of bringing iOS 9’s UIStackview to devices running iOS 6+.
This animation from the readme shows OAStackView in action:
You can find OAStackedView on Github here.
A nice port of UIStackView for older versions of the iOS platform.