This is the first of eight articles about how web apps work on iOS, and it has less code than the rest. Here I look at where the oddities come from, the ones everyone who ships a PWA to the iPhone ends up living with.Open the of almost any PWA built in 2026 and next to the manifest link you'll most likely find the apple-mobile-web-app-capable meta tag. Safari's old reference says it plainly: "Available in iOS 2.1 and later." Version 2.1 came out on September 12, 2008, when the App Store had already been running for two months. So full-screen web apps on the iPhone showed up after Apple had turned to the native SDK, even though the story is usually told the other way round. PWA behavior on the iPhone is full of small details like this. Behind the icon on your Home Screen are twenty-five years of attempts to turn a web page into a program, and plenty of the decisions made along the way are still sitting in your code.