Some Matte Black iPhone 7 units have paint chipping issues46
A growing number of Matte Black iPhone 7 owners are reporting via Apple's Support Communities that the paint on their devices has chipped or peeled off. In most cases, the problem affects small areas near the side buttons or the speaker grille. However, in one particular case, the paint has chipped off from the rear of the handset - as you can see in one of the images included below. These issues can show up both with, and without a protective case.
The first peeled / chipped off paint problems have been reported in November, about 2 months after the iPhone 7 and iPhone 7 Plus hit the market.
Apple's iPhone 7 warranty normally doesn't cover cosmetic damages, so users discovering paint-related issues will likely not receive replacement devices.
If you own a Matte Black iPhone 7 or iPhpne 7 Plus, let us know if you've experienced anything similar to the problems depicted in the images and at the source link below.
source: Apple Communities via MacRumors