Learn how to make a multiple screens app using MAKEROID or any other similar server
Working with multiple screens in app inventor is simple, that allows you to have an organized app. You can use a screen to welcome your user , a second screen for the main app and other screens for things like settings or end screen.
In this tutorial we use tinyDB to share data in screens.
I show you how to use procedures
I think that it is not necessary to use one screen as a welcome, one as a Main Screen and One for Settings.
It makes the App Size bigger.
I think you should try to use Vertical Arrangements instead of multiple screens.