Here’s why the iPhone Duo’s hinge could be cracking the screen

The iPhone Duo's foldable screen is prone to cracking due to contact with the hinge, causing a stress hotspot that can break the screen. The issue is caused by the flexible inner screen pushing against a part of the hinge, making the screen extremely sensitive to damage. Apple has acknowledged the problem and is replacing damaged units. iFixit's teardown reveals that the hinge's design, including gears, springs, and joints, creates edges that can cause damage to the screen. The issue is particularly noticeable when the device is folded, with a black spot appearing where the metal hits the screen. Apple's design may need to be revised to prevent this issue in future models.