This version of the Presidents Quiz app introduces a couple of new features. One is the List Picker component, which you can see at work in the preview video. It provides the user with a list of options, letting us create multiple-choice quizzes, rather than just short-answer quizzes as in the previous version of the app.
The other feature is a complex programming construct known as a list of lists -- i.e., a list that contain sublists as its elements. The list of lists abstraction is a data structure that you will find useful not only in this app but it lots of upcoming apps.
Objectives: In this lesson you will learn to :
use the ListPicker component to provide choices to the user;
define and use a new programming abstraction, a list of lists.
