The Editor is very similar to the Entry in that it allows users to enter some free-form text. The difference is that the Editor allows for multi-line input whereas the Entry is only used for single line input. The Entry also provides a few more properties than the Editor to allow further customization of the View.
XAML
<Editor HorizontalOptions="Fill"
VerticalOptions="Fill"
Keyboard="Chat"/>
Code
var editor = new Editor {
HorizontalOptions = LayoutOptions.Fill,
VerticalOptions = LayoutOptions.Fill,
Keyboard = Keyboard.Chat
};