iPhone Duo uses enhanced Apple A20 Pro and graphite pipes in the hinge

The Apple iPhone Duo brings a whole range of innovations that see Apple breaking new ground. From a camera invisibly integrated into the display and the use of a foldable display to Apple's first 2 nm ARM chip, which is also used in the iPhone 18 Pro. Speaking to PCMag Apple's engineers have now revealed a few interesting new details about the inner workings of the foldable flagship smartphone.

According to them, there are differences between the Apple A20 Pro in the iPhone 18 Pro (Max) and in the iPhone Duo. While the chips offer the same performance, the foldable's processor has been expanded with a second display engine to drive both screens simultaneously. Even more exciting, however, is the newly developed cooling system. For one thing, Apple has used a new packaging process that places the RAM next to the SoC rather than on top of it. This requires more space on the motherboard but allows heat to be dissipated more effectively.

For another, the heat sink has been redesigned. A new material that Apple calls "metal over foam" transfers waste heat from the SoC to the vapor chamber, which is three times larger than the one in the iPhone 17 Pro. The rear display cover is made of a copper alloy and also contributes to cooling. Apple routes flexible graphite pipes through the hinge to thermally connect the two halves of the smartphone, effectively increasing the heat sink's surface area. The combination of the new chip and improved cooling system is said to enable 35 percent better GPU performance under sustained load than the iPhone 17 Pro, despite a significantly thinner chassis.