Of the millions of Apple charging cables you find on the market, not all are certified by Apple. These are unsupported/uncertified accessories which you should avoid using (due to security issues that can damage your iPhone.)
When you try to connect such a cable to your iPhone/iPad, you might occasionally hit a snag. The iPhone/iPad will show a “This cable or accessory is not certified and may not work reliably with this iPhone” error and the charging might stop. There’s a workaround for this in the form of a Cydia tweak called Support Unsupported Accessories 8.
We don’t recommend using an unsupported accessory to charge or transfer data on your iPhone/iPad (due to the high risk of physical damage to the device) but just in case you want a quick fix for that tiny charge up or a quick file transfer, you might find this tweak useful.
Support Unsupported Accessories 8 gets rid of the popup message that eventually stops the cable from functioning.
You don’t have to configure anything and there is nothing to tweak. Just install and you should be able to use the cable without that error message showing up.
I’ve also seen that sometimes the error message shows up even with a certified cable (in one instance, even with Apple’s own charging cable). With Support Unsupported Accessories 8 Cydia tweak, you’ll be able to get rid of the error messages once and for all.
Apple produces premium products and accessories. This is why even the charging cables are costly by usual standards. While it’s always recommended that you use the original accessories – or Apple-certified ones (that come with the MFI tag) – a lot of people pick cheap accessories off the market.
Most of these aren’t certified by Apple. And Apple mostly prevents you from doing this by showing that error message.
While the tweak will help you overcome this, you will have to be very cautious. Uncertified cables have been known to burn iPhones.
Support Unsupported Accessories 8 is available for free from the BigBoss repo. It has been tested on iOS 8 versions up to iOS 8.1.1.