On Friday last week my phone just died, tried pretty much everything to recover it, but found on the net that there is no hope.
Took it back to apple store where they exchanged it for a “new” one. got home everything was fine until I’ve noticed that the connector was very dirty and dusty. Didn’t want to clean it as I wanted a new one(read on the net that those exchanged ones are actually refurbished. So got there today Monday and explained the situation. Within few minutes I was holding a “new” phone again with a dirty connector 
. I said that this is not right but they replied that all “new” replacements are actually refurbished phones, so because it was much better then the other one, I took and will see when it’s gonna die again.