More like a noob question

[yellowtrr]

Where I am supposed to write the name of the .py file I want to change to .apk on bulldozer.spec?

[inclement]

You pass buildozer a path to a folder (this is one of the options). It pacakges this folder, and will start the app from a main.py file. If you don't have a file with this name, add one and write in it the code to start your app.