What happens when the user clicks on an app shortcut to launch the app?
Remember that your app is actually hosted on the AppSheet mobile runtime. So when the user launches your app, it first loads AppSheet (which you do not see) and then starts your app. The whole process only takes a few seconds, after which the user can start using your app. Your app looks and behaves exactly as it did in the emulator on our website.
You can find out how to install your app to your homescreen here.