You can create new objects and add in data for those objects using a single import. This article section shows you the steps for doing that: Creating a New Object Via Import.
Pages, Views, and Other App Elements
Right now there isn't an option for importing pages, views, or other app elements into your apps. Pages and views can be copied within the same app:
You can also copy an entire app with its pages and views as the starting point for a new app: Copying Apps.
Otherwise, you will need to manually recreate the pages and views in your app.