iOS 7 detects when non-certified Lightning cables are connected and issues a mild rebuke, presumably intended to gently encourage people to buy certified (read: quality certified by and money generated to Apple) cables …
Despite the message, non-certified cables do function properly. Given that iOS 7 can detect them, Apple could have opted to block them from functioning, but presumably knows that would upset some of its customers, so has chosen a more subtle approach this time around. Next time it might be, “Hey, this is a $800 phone, you can afford a $20 cable you cheap bastard”.
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