Apple Reveals Hinge and Cooling Details for First Foldable iPhone

Apple has revealed specific design details for the hinge and thermal management system of its upcoming foldable iPhone, dubbed iPhone Duo. The information was shared by Apple executives in an interview with technology publication PCMag.

Dan Murray, Apple's Vice President of Chip Engineering, and Banafsheh Barabadi, Senior Manager of Thermal Product Design, discussed the company's custom cooling solutions. These advancements are aimed at maximizing the sustained performance of the A20 Pro chip in the iPhone 18 Pro models and the iPhone Duo.

The A20 Pro chip features a wafer-level multi-chip module (WMCM) design, relocating DRAM adjacent to the processor instead of stacking it above. Apple states this creates a direct thermal pathway from the chip to the vapor chamber, resolving thermal bottlenecks found in older "package-on-package" (POP) configurations.

For the iPhone 18 Pro, the vapor chamber's surface area is three times larger than in the iPhone 17 Pro and contains more deionized water. This chamber also serves as a structural component. The iPhone Duo employs a thinner vapor chamber positioned centrally. Its hinge incorporates flexible graphite tubes to connect thermal structures on both sides, facilitating heat dissipation within the folded device.

Apple claims these new thermal systems support demanding workloads like gaming, video recording, and on-device AI. The iPhone 18 Pro offers a 35% increase in sustained GPU performance, while the A20 Pro's CPU performance is up by 20% compared to the iPhone 17 Pro.