Touches, Presses, and Gestures
Encapsulate your app's event-handling logic in gesture recognizers so that you can reuse that code throughout your app.
If you build your apps using standard UIKit views and controls, UIKit automatically handles touch events (including Multitouch events) for you. However, if you use custom views to display your content, you must handle all touch events that occur in your views. There are two ways to handle touch events yourself.
An object that describes a single user interaction with your app.
An object representing the location, size, movement, and force of a touch occurring on the screen.
An object that represents the presence or movement of a button press on the screen for a particular event.
An event that describes the state of a set of physical buttons that are available to the device, such as those on an associated remote or game controller.
Peek and Pop
Use 3D Touch input to display custom previews and actions for your content.