Can I trade iPhone 4S for iPhone 5?

My lock button won't work anymore on my iPhone 4S. And I was wondering if I take it in, will they give me an iPhone 5. My friend went into the apple store with a defective iPhone 4 and they have her the iPhone 4S. Would the same happen to me but only with the 5?

They give you whatever phone they have that's closest to the phone you have. Since the 4S is still available, that's probably what you'll get. But if they don't have any 4S's, you might get a 5 instead… You never know!

You would have to pay more, why do you think you could upgrade to a better phone for free?