Yes you can view your work as you progress with your app. All you need to do is to share the app with you when you want to check it's progress and how the app looks on iPad. For more information check our section in our user guide:
http://help.interactbuilder.com/m/16264/l/164263-share-your-app

For the download of a book situation you can use the share process. Here is the information for the share process:
http://help.interactbuilder.com/m/16264/l/164263-s...

Thank you for your feedback.

From what I know you can't upload a photo from the user camera roll.

I was able to recreate this situation and I forwarded it to our lead developer. Thank you for your feedback.