If the app loads and launches, splendid! Time to look at your Collections and check on your process.
Your top-level collection needs to have a collection in it (I'll call it "Launch") --
Launch needs to have content (articles, banners, additional collections) Like this:
(Articles, banners, etc.)
When you first start the app, Launch will appear and show the articles, banners, etc that it contains.
Launch will also appear in your App Menu.
Now about seeing things.
I hope you're using a Preview app. It's an option when you setup the app (first screen for all app building)
If you are using a preview app and you want to see your stuff, click the Preview icon in the upper right corner of the Portal -- wait for the progress bar to finish, then breathe before going to your device. Change views or relaunch the app to see update bubbles.
For more detailed info and guidance, refer to the Getting Started Guide and HELP.