Hello, guys! I am from another country and my iPhone 5s, bought in USA, stopped working (no water damage or any other damage, just doesn't power on). My friends go to US tomorrow and I give the this iphone to exchange in the Apple Store. Could you please explain me please, how this process goes? They just come to the store, give the iPhone to a rep, say it's broken and wait for a new one to get? Or anything special is needed? Thanks to everyone in advance!