It took a sharp dip in iOS 7 when Jony Ive took over for Scott Forstall, but it's more than recovered. The gesture navigation on home-buttonless iPhones is a revelation, and makes the original, button-based system look clumsy in comparison (it's no surprise Google more or less copied it wholesale in Android 9). And it's almost physically painful to go back to a phone without the universal back gesture, despite it never having existed in early versions of iOS.