How to add dynamically UI module in android?

I want to build android app (App1, App2, App3 and etc - Achieve this by product flavors in gradle) from my single source code.
1. App1, App2, App3 and etc has some feature. Functionally same but UI may different for each Application
2. Features are module. Feature can be added by gradle scrip (flavor).

My question is, I am ok with functionality. How can i dynamically add UI module?