1 - create the <name-of-the-app> app with python manage.py startapp
2 - move <name-of-the-app> directory to <project_slug> directory
3 - edit <project_slug>/<name-of-the-app>/apps.py and
change name = "<name-of-the-app>" to name = "<project_slug>.<name-of-the-app>"
4 - add "<project_slug>.<name-of-the-app>.apps.<NameOfTheAppConfigClass>", on your LOCAL_APPS on config/settings/base.py