With Control Center, Apple is bringing users quick access to certain features of the operating system, like toggling on/off Bluetooth and WiFi. Now you would think that turning these features on/off via Control Center would do what it’s meant to do, but apparently that is not the case because despite being toggled off in Control Center, they aren’t fully disabled.
You might think that this is a bug but in a support document posted on Apple’s website, it seems that this was done on purpose. According to Apple, “In iOS 11 and later, when you toggle the Wi-Fi or Bluetooth buttons in Control Center, your device will immediately disconnect from Wi-Fi and Bluetooth accessories.”
However they note that Bluetooth and WiFi will continue to be available for use with certain features of the iOS device, such as AirDrop, AirPlay, Apple Pencil, Apple Watch, Continuity features, like Handoff and Instant Hotspot, Instant Hotspot, and Location Services. Users who want to fully disable Bluetooth and WiFi will have to go into the Settings menu to do so, and not via Control Panel.
We suppose this could be rather confusing for some users so it’s something to take note of if for whatever reason you want to fully disable Bluetooth or WiFi on your iOS device.