Key Concepts: Gesture Recognizers
UUINavigationController is a pretty important navigation component and an easy way to make your apps look pro.
GestureRecognizers are the optimal way to get user interaction from user touches. GestureRecognizers have all the math worked out for pinching, swiping, double-tap, etc. Recognizers also allow for IBAction hook-up so they are treated just like a UIButton.
Moving a view to a location on the screen can be easily accomplished by altering its transform. Altering the transform of a view does not physically change the frame, it merely describes how the view is drawn. This can come in handy when re-setting UI components.
Autolayout is a very handy yet somewhat complicated way of positioning UI elements consistently across device screen sizes. Autolayout will be explicitly covered later in the program.