I recently noticed my iPhone 5 heating up while it was charging. I tried switching chargers and that didn't help. A few days later I noticed that my screen seemed to be separating from the body. You can see in the pictures below. The bottom of the phone is coming apart. I called my carrier AT&T and they explained that I was eligible for an upgrade. I would have to pay for that upgrade of course so I explored other options.
Here's a close up of the separation.
The phone was functioning as normal with the exception of a small screen defect that you could barely notice. If I pressed hard enough, I could snap it back into place for a short time.
I decided to Google the problem and see if I had any options. I found that several other people were experiencing this same problem.
A few people said they took the phone to Apple and others said to just buy a new phone. I figured that it was worth a try to start with Apple. I backed up my phone and headed to Apple to see if they could help me. Upon arriving, I was greeted right away by a friendly Apple associate. I explained the problem I was having and he asked to look at my phone. It took him about ten seconds to see that the screen was separating from the body. He explained that it was covered under warranty due to the battery swelling. He further explained that the phone would be replaced at no charge. He sent me to a different station to meet with a tech. Within about five minutes the tech brought out a new phone and began setting it up for me. The whole process went very quickly. I had my new undamaged phone and I was on my way.
If you have a problem with your Apple product, I would suggest starting with them before going to your carrier. This could save you time and money.