I was stuck at work way longer yesterday than I thought and my ip4 was in the car the whole time. It was cold, but not near as cold as the 0 degrees the manual says it can be stored at. The phone was almost fully charged and when I came out of work, it was dead. I tried to charge it all night long, still wouldn't power up. I held down the home button, no good. Hold down the power at the top, no good. Held both together, no good. So, can I just show up at the store or do I need to make an appointment? If it won't power on seems to me that I should be able to show up and they should fix it or replace it on the spot.