Apple’s already told you that you should be using the official lightning connector cables, although some of you are likely to have just taken it as helpful advice more than a command.
In iOS 7 however, you don’t have a choice, with the company now blocking some third-party lightning connector cables, with those not containing Apple’s certification chip being those that aren’t making the cut.
If your cable is unofficial, then the advice is to buy a Certified one — and it doesn’t have to be from Apple itself, some established accessories manufacturers are also certified as they pay Apple for the privilege and make them to a specific spec.
Of course if you’d rather use your uncertified one, then there’s nothing stopping you either, with some advice coming from some helpful iPhone owners:
Turn on USB power
Plug in lightning cable to iPhone
Dismiss any warnings
Unlock your iPhone.
Dismiss any remaining warnings.
Now with the screen turned on.
Unplug the knock off lightning cable.
Plug it back in.
Dismiss warning again
It should now charge.
It’s probably a lot more logical to just go out and buy a certified cable.
Source: 9to5Mac
