Joe Rossignol, MacRumors:
Even when toggled off in Control Center on an iPhone, iPad, or iPod touch running iOS 11 and later, a new support document says Bluetooth and Wi-Fi will continue to be available for AirDrop, AirPlay, Apple Pencil, Apple Watch, Location Services, and Continuity features like Handoff and Instant Hotspot.
Toggling off Bluetooth or Wi-Fi in Control Center only disconnects accessories now, rather than disabling connectivity entirely.
I don’t toggle either Bluetooth or WiFi so I didn’t notice this, but I also didn’t think to check whether Bluetooth was, indeed, switched off if I toggled it off in Control Centre. I kind of get why this change was made: a frequent barrier in my use of AirDrop “just working” is that a friend’s Bluetooth connection has been toggled off. I don’t think that most people would be fully aware that both networking services must be switched on for many of Apple’s “continuity” features to keep working.
Still, this does feel a bit wrong. A toggle switch that looks like it’s on or off should behave accordingly. There are some indicators of its true behaviour — when you toggle WiFi from Control Centre, a message across the top of the screen reads “Disconnected from WiFi Network Name”. This doesn’t say that WiFi will continue to be available for iOS features, though, and it seems counterintuitive.
Update: Changed “affordances” to “indicators” per a reader’s emailed suggestion.