This happened to me while I was shopping for groceries and I didn't even drop my phone, it was safely sitting in my pocket.
Although over the years it got its share of bumps on pavements, rocks and other rough surfaces, and got used in the rain to the point that the screen started flickering.
Funny that it finally gave up while being treated gently recently.
Weird thing is - when I try to unlock the phone, the capacity buttons blink a fee times before the phone goes back to sleep again. I didn't notice that behavior while the screen was working.
Soft reset was the was the first I tried but that didn't avail.
It seems it's time to get a 950 already.
Worst part is: I cannot access the contents of the phone when connecting to PC. Probably cause it's pin-protected.