Which accessories actually fit the iPhone Duo?

The new dimensions are an opportunity for manufacturers to try new approaches with accessories. For example, ESR's vegan leather magnetic case protects the entire phone, including the hinge mechanism, and has a movable kickstand that doubles as a lens protector. Mous offers a thin aramid case manufactured using the same material used in body armor. While it lacks hinge protection, it adds just 1.7 mm to the 11.3 mm maximum thickness of the Duo. Spigen's cases use the iPhone's folding mechanism as a stand, while the Spigen Armor case offers much more robust protection.

Protection isn't just about the frame. Even if they fit, traditional tempered glass protectors will crack when you snap the phone shut. When purchasing screen protection for the iPhone Duo, you should seek flexible TPU (thermoplastic polyurethane) or PET (polyethylene terephthalate) film protectors designed for the foldable device. While less scratch-resistant than glass, these films can handle repeated folding and won't crack when snapped shut.

Apple promises a future software update to enable the USB-C Apple Pencil to work with iPhone Duo . Unlike the Pencil 2 or Pro, the USB-C model has its own independent charging and pairing facility using USB-C. Supporting the other models would have required the smartphone to host an additional high-power wireless charging coil capable of external-facing power exchange, which would have added to the device's thickness, cost and weight.