Apple has unveiled the iPhone Duo, its first foldable iPhone, with sales set to begin October 23. The new model opens to a 7.6-inch inner screen and carries a 5.4-inch outer display. U.S. prices start at $1,999 for 256GB of storage. Preorders begin October 16 across more than 70 countries and regions. The iPhone Duo uses a book-style design with a precision hinge built from more than 100 components. Both displays support ProMotion, Always On features and peak outdoor brightness of 3,000 nits. Photography centers on two 48-megapixel rear cameras covering main and ultra-wide shooting. Apple powers the iPhone Duo with the A20 Pro chip, also used in the iPhone 18 Pro models. The company rates mixed use across both screens at up to 24 hours per charge. Video playback reaches up to 31 hours on the inner screen and 44 hours on the outer display. iOS 27 supports folding interface as October rollout approaches.