You can add as many pages and feeds to your App as you like. Think about what features you wish to provide your users with and choose accordingly, you can always remove or add pages to your App during the creation process.
How to do it
To start adding them click on the Content tab at the top from your dashboard:
And select the pages and feeds you like from the left hand sidebar menu:
Click on the pages you wish to add or simply drag and drop them in the feed list. You can change the disposition of each page at any time.
Pages and feeds include different types of content, which you can import from your computer, create from your dashboard, or link via URL.