> It only exists on Android because it started off as a non-touch OS. That doesn’t really make sense, it has very little to do with the actual interaction. It

> It only exists on Android because it started off as a non-touch OS. That doesn’t really make sense, it has very little to do with the actual interaction. It seems Android apps were originally envisaged as a collection of islands rather than one solid block. In that context the back button does make sense, you’d be jumping from “activity” to “activity” rather than app to app, and the back button would provide a logical thread through all of that. But it didn’t work out that way at all, apps became just as centralised as iOS ones and the back button’s original functionality became kind of vestigial.