Connecting the dots: iFixit recently dismantled the iPhone Duo to gauge its repairability and find out why so many units are being returned with broken screens just days after going on sale. The investigation could not determine the exact cause of the damage, but the team behind the teardown has proposed three plausible hypotheses based on CT scans, 3D modeling, and breakage patterns.
According to iFixit, the most plausible reason for the breakages is a malfunctioning central support bar inside the hinge. The bar is supposed to retract each time the phone closes, but it's likely failing to pull back far enough, which makes the curved part of the inner display press down against it. Repeated over time, this creates a stress point and eventually cracks at that location.
Another possible culprit is the curved rails that guide the hinge's movement. Investigators found that the rails are designed to rise above surrounding components during folding, but they could collide with the screen with even the slightest misalignment, causing the reported cracks and other damage.
The final hypothesis is that the damage may stem from a design flaw rather than any single misbehaving component. According to iFixit, several internal structural edges and components converge right at the transition zone between the opening for the cable connecting the two folding halves and the central hinge support, putting severe stress on the display.
Since many of the reported failures appear to be concentrated around this transition area, the experts believe that repeated opening and closing is producing an inordinate amount of stress that the ultra-thin display layers, which measure barely a few microns, are unable to cope with. This, they say, could lead to catastrophic damage to the screen in some cases.
iFixit also found that despite its IP68 rating, the Duo still allows fine dust particles to get into its hinge mechanism, causing a disconcerting crunching sound that could indicate potential damage to both the hinge and the screen. However, it still reportedly lets in less debris than rival foldables like the Samsung Galaxy Z Fold 8 and Pixel 11 Pro Fold.
The teardown also determined that the iPhone Duo is one of the "most repairable" foldables on the market, which is surprising for an Apple product. iFixit gave it a provisional repairability score of 5 out of 10, which is disappointing in the larger scheme of things, but still higher than any other foldable has managed.