Используйте приложение APKPure
Историческую версию Admob Example можно получить на Android
Образец приложения AdMob
Sample App AdMob
===========
Sample App AdMob is an Open Source Android that allows developers to easily create applications
with AdMob SDK.
Feel free
to use it all you want in your Android apps provided that you cite this project and include the license in your app.