If you are using an emulitor on a iPhone unfortunately you cannot play with each other because ROM'S do not interact with each other sorry :/
Your question is very long and it is mixed up making it for me to understand it and answer it.Please make it clear so that I answer it.
Yes, you can.
yes you can
No, its against Apple policy to play real money games.
u need an emulator first if they have 1
unless it's an iphone yes i don't know about the others.
no u cant stupid
You got to play combat training and have your friend sign in with a different controller
Very unlikely. It only partially works on an iPhone 4S, so an iPhone 4 would probably be unable to play.
trading cable genius
There are a few different things you can do with Pokemon. You can play against people or you can collect the cards.
You can ask for a friend if they don't play Pokemon anymore and they can give it to you. Other than that it is impossible.