iOS 19, set to be unveiled at WWDC 2025, will remove support for three oldest iPhone models running iOS 18.Apple has to remove older iPhones from the list of supported devices to meet the new requirements of upcoming iOS releases.Contradicting a report, not all iOS 18 phones will run iOS 19 this fall.iOS 19 introduces an exciting new design, but it won't be compatible with all iPhones running iOS 18.