App Versions and sub app

I would like to have information on version and sub app management.
I have two applications that I would like to see do the same thing but whose design will be different. One is one is the sub-application of the other.
From what I understood (you will tell me if I am wrong), to achieve this, I need to create a version of my main application where I will make the color and design changes and this version will be pushed on the sub app.
So I did that.
It seems to me that every time you push, you push the basic version (even if you sync and deploy the seconde vesion before) and not the second version whose design is changed.
Can someone explain me