Ok, so I dropped my iPhone 4 on the ground and the back of it kind of crack and I have some scratches on the back, if I take it to get repaired, is there a way where they can just fix the back or do they have to do something else?
Is the iPhone still functioning normally?
Apple probably won't. If you take to a 3rd party store they can usually repair pretty cheap. My mom slammed her iPhone in the trunk like 5 times w/o realizing it. She took it to one of those stores, and got it fixed for around $40. That was the screen and everything though.
Yes, if you have warranty they will replace it for you!
I reocomend a otterbox case btw
Probably only if you have warranty, they'll fix it free. If it's just a back crack then they won't have to take it apart.
As far as I know that if you have a warranty it is free, I cracked my iPhone thrice and they charged me $80 for replacements. Contact Genius Bar and hope you get some decent advice. If they are unable to solve your problem then they will ask you to pay $80 and you get the replacement. I would not recommend going through 3rd Party as it will most probably void your warranty.
Take to a Apple Genius bar they will fix of course not if jb though