Xamarin.Forms has common APIs to describe cross-platform mobile user interfaces.

The description of the UI is categorized by pages, layouts, and controls. We will explore each one of them in this chapter.

Each page, layout, and control is rendered differently on each platform using a Renderer class.

A renderer creates a native control corresponding to the Xamarin.Forms representation, arranges it on the screen, and adds the behavior specified in the shared code.

In this chapter, we will implement our own custom Renderer class to customize the appearance and behavior of a control.

Custom renderers for a given type can be added to one application project to customize the control in one platform while allowing the default behavior on other platforms.

Custom renderers can be added to each application project to create a different look and feel on iOS, Android, and Windows Phone.