Recently I smashed my iPhone 4S, and since I planned on getting it fixed I switched phones for awhile. I tried turning my iPhone back on, but that didn't work. I charged it and the apple wouldn't come up, I tried plugging it into my computer and that wouldn't work either. I had it plugged in for the night and that didn't help either. I then tried to reboot it, or put it in DFU mode and that hadn't worked either. I was going to take it to Apple just to replace it, but I wanted to try everything I could to at least turn it on. I plugged it into my car charger and it turned on, but it would immediately turn off after trying to open an app or after being in an app for a few minutes. I don't really know what to do from here but I wanted to know what people think I should do?