Foldable iPhone production stalls due to hinge issues

Test production of Apple’s long-awaited foldable iPhone, likely called “iPhone Ultra,” has hit a significant technical hurdle centered on hinge reliability, according to a known leaker.

The leaker known as “Instant Digital” posted on Weibo that the foldable device’s hinge still does not meet Apple’s quality control standards under prolonged and high-frequency opening and closing conditions. The leaker described the problem of mechanical wear and tear as one that “must be addressed with absolute perfection, otherwise progress will simply have to be stalled for the time being.”

The hinge has been a key part of Apple’s foldable device development for years. Supply chain analyst Ming-Chi Kuo first reported that the device would use liquid metal components in the hinge mechanism, with Dongguan EonTec serving as the exclusive supplier of the amorphous alloy. Instant Digital then explained that the material, also known as metallic glass, features a disordered atomic structure that is more resistant to bending and warping than traditional metals and more durable than titanium alloy. This makes it suitable for the hinge of a foldable.

Apple previously only used the material in small components such as SIM card ejector pins, so the ‌iPhone Ultra‌ would mark its first major use in a critical mechanical part. A subsequent report released in January corroborated plans for liquid metal hinges, noting that Apple had been exploring the material for more than 15 years, dating back to a 2010 licensing deal with Liquidmetal Technologies.

Screen creasing is a concern that has followed the foldable smartphone category since its inception. Instant Digital claims that Apple has essentially accepted a certain degree of crease as inevitable, but that test results have demonstrated that the device can maintain a visually crease-free state over the long term. This is consistent with previous reports: leaker “Fixed Focus Digital” reported in February that production orders were placed with a fold depth of less than 0.15mm and a fold angle of less than 2.5 degrees. Apple has reportedly sought to eliminate the crease “regardless of the cost”, with technical solutions including an ultra-thin, dual-layer glass structure designed to distribute mechanical stress across multiple layers, and advancements in optically transparent adhesive to hold display layers in precise alignment.

A follow-up article from the leaker suggests that the hinge difficulties are unlikely to delay the device’s planned release window somewhat, noting that there is still plenty of time. This is broadly consistent with previous reports: DigiTimes reported in April that production was about one to two months behind schedule, but that a fall 2026 launch remained on track, with mass production expected to begin in July. Apple is expected to announce the foldable iPhone alongside the iPhone 18 Pro models at its September event, although some reports suggest customer availability could decline until December.

In a third article, Instant Digital offered a note on the device experience, suggesting that despite its larger form factor, the foldable feels like an iPhone rather than an iPad when in use. The leaker added that the screen size offers limited practical utility for a stylus, casting doubt on whether Apple Pencil support would be a meaningful feature for the device.

The foldable iPhone is expected to feature a 7.8-inch inner display and a 5.5-inch cover display, with an A20 chip, C2 modem, Touch ID power button and dual rear cameras. The price is rumored to be around $2,000.