How to know when your iPhone 4s is real?

For some description, Someone sell it to my daddy. The box has nothng but the iPhone picture on the up view and There's ''4s'' in the bottom. Well i put water on the screen and the water just roll. Answer please!

Also how to go back. I can't see any ''return'' button.

This is the "Gambling" section. Daddy should bring it back to the "someone" they bought it from and ask them. It sounds like it's either a cheap Chinese counterfeit, or it's stolen goods, or both.