Sorry for the long post. I just wanted to explain the whole problem. Thank you for everyone who takes the time out to read it and to help. Much appreciated. So I've had my trusty 3GS for nearly 3 years now, and never had an issue...until late August. I was using my phone as I normally do, and the battery was nearly full (about 80% charge). I was using my 3G while I was walking out and about and, suddenly, my iPhone just...cut. It turned off. And not in the way it turns off when you manually turn it off, or when the battery dies. It's like it crashed. You could see a ghosty image of what you were looking at before it happened, but the image wasn't in it's entirety either. It looked a little sketchy, with lines across it that weren't off the image, but just plain black. The image then slowly fades away. To make matters worse, it refused to turn back on. I kept trying. I held both the on/off button and the home button, just the on/off. Different durations of time holding it, left gaps before I tried again. But all the happens is the Apple logo shows for some time, then it cuts again. Once or twice, it turned back on and the lock screen showed. But turned off nearly right after. I also noticed something with the battery...it seemed to be draining very quickly. After about an hour or so, I was then presented with the "Battery low, charge" logo. I think I might have noticed this once, maybe twice, earlier in the month. But it only happened when the battery was very low (about 5%-10%). So I thought maybe it happened because the battery was low. But I didn't understand why it happened this time. It never really happened again after this unless the battery was very low. But it's now gotten much worse. Nearly everything I do seems to mess it up. Using 3G, using WiFi, phoning, texting. Music seems to be fine (so it's become a glorified iPod??). I have tried doing a factory restore. But the problem is, after restoring, it asks where you want to restore data from. Of course, I need my data back on my phone, so it seems a little pointless to do a factory restore, because what if it's an app I have downloaded or some data. It's going to come back on my phone, and it's going to happen again, if it's a software problem. Something to note, when I plug it back into a charger, it turns back on. It would make you think it is a problem with the battery, but it happens at various percentages and after various amounts of usage as well. I can have it in my pocket for 7 hours and maybe I try ringing someone at 60% and it'll crash. Or I could have had it off-charge for 1 hour, try checking my email and boom. Also, it doesn't happen every single time, but has just started happening very regularly. And another annoying thing is, is it seems to be, to an extent, resetting what I did previously. So if I listened to 3 songs, after it crashes, it will be back at the beginning of these 3 songs. Other software issues are happening too. For example, I check 3 emails, at the top it just says Inbox (as in all are checked). I leave that inbox, and it says 3 next to that inbox. And, of course, same problem as the music. I phoned Apple. They want to send a replacement for £126. But I want to know what is actually wrong with it. And maybe how to fix it. I don't just want to fork out that kind of money without some kind of explanation of what's wrong with it.