No supplier has been verified as responsible: reports have named FineMTEC and Shin Zu Shing, but neither has been tied to the defect, and Fine M-Tec has denied that its parts caused the failures.

Apple has not announced a recall or broader replacement program, or published a serial-number checking tool; customers with screen problems should seek an assessment through AppleCare.

Apple’s iPhone Duo launch has been overshadowed by reports of cracked inner screens, white pixels and damage along the central crease, a controversy dubbed “Crackgate.”

The failures were reported soon after the first foldable iPhone went on sale on October 23, with some owners describing hinge resistance or a popping sound before a crack or bright line appeared on the display.

A leak points to defective materials from one hinge-component supplier as a possible cause, rather than a fundamental flaw in the folding design, but Apple has not confirmed that explanation.

An iFixit teardown raised a different possibility: that the hinge’s support structure or curved rail may not retract properly, putting pressure on the screen; neither the mechanical-design theory nor the materials explanation has been established.

Apple says the display problem affects a small number of iPhone Duo units and advises owners with faults to contact AppleCare for a free replacement.

Chinese leaker Kang says serial numbers may help Apple identify potentially affected production batches, though the report is unverified and the number of affected phones is unknown.

Despite the reports, the first pre-order batch sold out, and some resellers listed units for as much as $5,000 against the $1,999 starting price.

The strong demand means the iPhone Duo cannot yet be called a commercial failure, though cautious buyers may prefer to wait for a rumored successor that could add Face ID and a triple-camera system.

Counterpoint Research estimates Apple could sell about 6 million iPhone Duo units, roughly 22–30% of projected global foldable-phone shipments this year.