Setting-up on Androids

I have a Droid which is hooked up to the internet. My granddaughter has my old Droid and it is purposely NOT hooked to the the internet. She likes to play games on it. How can I download games from Google Play Store and get them on her Droid? How can I download Apple App Store games and get them on her Droid? As she is without internet how can I set-up Airdroid on her Droid?

Also, how do I setup AirDroid on my Droid?