Sunday I started having problems with my iPhone 6+, where it would sometimes “wake” into a half-gray screen state where the touchscreen didn’t work. By mid-day Monday, it was doing that at least 9 out of 10 times. I made a Tuesday appointment at the Apple Store, because this seemed like probably a hardware problem but decided Monday night to try going through the recommended online trouble-shooting steps.
Force-restart - no help. Restore - well, first I had to get it to wake into the normal mode so I could get to the Settings app, turn off the “Find my iPhone” feature (Was it necessary to do that in previous IOS versions? I didn’t think so) and be able to enter the passcode, but I did get it restored and that was no help. I then tried to update to IOS 9.2.1 in case it was some kind of weird bug fixed in the latest.
It occurred to me, much too late, that Restore and Update are really bad things for Apple to recommend for people to try if they’re having problems with their touch screen, because after you update you have to enter the passcode and can not wake it with a fingerprint, but if your touchscreen doesn’t work, you can’t enter the passcode, and if you fail to enter the passcode too many times the phone will disable itself. Whether or not it got into the disabled state, it was in a bad way by late Monday night. It sat like a lump, the screen was resolutely black, and it would not execute a Force Restart, go into iTunes recovery mode or show any sign of life at all despite its supposed 90% charge. I woke up at 4:15am and lay there wondering whether I had fully bricked it, whether Apple would try to lay the blame on me if so, and whether I’d soon be posting this on the “Apple bricks phones” thread.
When I finally got up and plugged it in to mess with it some more, it came on with the low battery indicator meaning it was alive but had drained over night. Relief! I got it partly charged, and eventually got it to wake into the right state so I could put in the passcode and get it semi-working again.
To cut to the chase, I took it in to the service appointment at 11:30, they diagnosed a hardware fault, and I walked out of the store around 12:00 with a brand new phone, no charge, complete replacement under warranty. 
This looked like it was going to be a Fuck Today but it turned around instead. Victory!
