For example, if I want to activate the flashlight on my iPhone, I have to know to swipe up from the bottom left-hand corner in order to bring up a control panel where the flashlight button exists. There is absolutely nothing on the interface that indicates this is an available action. That might be fine if the action were intuitive or if it had some prominent affordance, but short of having read the iOS operation manual that is included in the box with the iPhone (oh, wait, no user manual is included in the box), there is no way to know this control exists. It is the quintessential hidden control—useful, lurking, and available—but only to those who know the trick. Want to see notifications on the iPhone? That's a separate hidden control, swiping down from the top corner this time. Apple Pay? Press an unlabeled, multifunction button twice. The number of hidden controls makes even simple operations difficult.
GET THEIR ASS