I cannot remember which IOS update first caused this, but I've been frustrated by the fact that it requires two presses of the Power/Lock button on the side of my IPhone 5S before the screen locks. The first press seems to bring me to a notification pop-up showing me the most recent notifications, and only after pressing the button again does the screen lock. Can anyone confirm this behaviour, and suggest how to change the situation so that a single press of the switch wil lock the screen? Thanks.