For about a month, my iPhone 5 was troublesome when charging. I had to press the connector in very hard, or wiggle it from side to side, or prop the phone up funny to get it to charge. Today, it wouldn’t charge at all no matter what I did.
I tried multiple cables and everything I could think of. Finally, I shone a bright light into the lightning connector, and it seemed like the hole wasn’t deep enough. I was in the office, and didn’t have anything other than a paper clip to probe down in the hole, so I shut the phone completely off and probed in the hole with the bent paper clip.
I couldn’t believe the amount of lint that I was able to pull out of the hole. I don’t recommend using a paper clip, as you might damage the lightning connector or short something out, but a toothpick will work just as well.
Take a look at what came out of the lightning socket.
I am guessing that a few bits of lint fell into the socket every time the phone was placed in my front pants pocket, and when I charged the phone most every night, the connector did an excellent job of tamping the lint down, compressing it into the dark recesses of the socket. Not a problem, until enough lint built up to the point where the connector could not make a good connection.
So if your phone isn’t charging, make sure that the socket isn’t full of lint.