Apple’s first foldable iPhone, widely expected as a premium book-style model with roughly 7.8-inch inner and 5.5-inch outer displays, remains on track for a September 2026 debut alongside the iPhone 18 Pro lineup, according to Bloomberg’s Mark Gurman and supply-chain reporting. This timeline underpins the market’s 83% implied probability for a pre-2027 release, as Apple prioritizes the high-margin device over a standard iPhone 18 model that may shift to 2027. Engineering validation has advanced, with progress on crease reduction and hinge durability, though limited initial supply and potential late-year shipping remain noted risks. Traders are weighing these factors against Apple’s historical ability to meet flagship deadlines and competitive pressure from Samsung’s established foldables. The September event serves as the key near-term catalyst.