An ongoing three-week livestream stress test has shown signs of hinge wear on the iPhone Duo after more than 451,000 folds. Testers report the mechanism began to feel looser around 390,000 folds and, by roughly 440,300 folds, the screen no longer opened fully before the folding machine closed it again.
iPhone Duo hinge behavior and immediate findings
Testers said the wire used to open the screen would withdraw before the display reached the fully open position, after which the screen would “coast” the rest of the way. Between 12:30 and 1 a.m. during the test—around the 440,300-fold mark—the automated Fold-a-Phone device caused the screen to begin closing before it had time to open fully. At that point there was no distinctive snap; the screen sat about 5 to 10 degrees short of the fully open position and could still be opened fully by hand.
The iPhone Duo remains mounted in the folding machine and the test is continuing. The device is still operational, maintains other screen positions, and shows no signs of cracking or other failure so far.
Display sourcing, durability context and projected lifespan
The iPhone Duo uses OLED panels sourced from Samsung Display. Samsung’s screens have undergone certified third-party fold testing, and the display used for the Galaxy Z Fold7 passed a 500,000-fold durability test. Testers note Apple probably isn’t using an off-the-shelf Samsung display, but current testing suggests the iPhone Duo’s OLED panel is on track to match that level of durability.
The ultimate lifespan will depend on both the display and the strength of Apple’s hinge design. At about 450,000 folds, the iPhone Duo would equate to more than a decade of use at a rate of 100 folds per day.
Ongoing objectives and failure criteria
The testing team plans to continue folding the iPhone Duo until it reaches predetermined failure conditions, which include loss of power, sensors failing to detect the screen properly, and screen blackout. Apple has not shared results of any internal hinge testing it likely conducted, nor has it provided an estimated fold lifespan for the device.
The livestream continues on weekdays from 10 a.m. Pacific until 2 p.m. Pacific and will run until the iPhone Duo fails under the test’s criteria.
