https://www.theguardian.com/technology/2017/sep/21/ios-11-apple-toggling-wifi-bluetooth-control-centre-doesnt-turn-them-off >Quick switch simply disconnects phone from access points and devices rather than turning off the radios, in move criticised by security researchers >The new, redesigned Control Centre in iOS 11, which appears to allow users to toggle various settings such as turning wifi and Bluetooth off, doesn’t actually turn them completely off.