I have a iPhone 4S. My mid frame bezel is kinda out of shape and my battery is dying to quickly. Had the phone for 1 Year 10 months. Will they replace the parts instore or replace the whole phone
Do you have extended AppleCare warranty?
Cause they come with 1 year and yours is expired. So if its not covered they won't do any repairs or replacement for free.
To answer your question differently: It depends on what needs fixed / replaced. For example, a broken iPhone 5 screen can be replaced or they can hand you a different iPhone 5.
I don't know what they'll do for an iPhone 4 battery but my expectation is that anything to do with the frame will be a replacement phone. Just a guess.