PROBLEM OF THE FORTNIGHT
Why is my iPhone joining public Wi-Fi?
Q My iPhone is being diverted to public Wi-Fi – even though it’s turned off! Only mobile data is set to On, in Settings. Any idea what’s going on?
Patrick Francis
A This is an interesting problem, and one that blasts a hole through the idea that Apple devices and software are always easy to use. It also demands a longer answer than your short question might suggest.
The crux is that there’s more than one way to switch off Wi-Fi on an iPhone, and those differing methods don’t do exactly the same things. In Settings, if you tap Wi-Fi followed by the Wi-Fi switch to slide it to its Off position, that, truly, is your iPhone’s Wi-Fi radio switched off. You would not see any prompts to connect to public Wi-Fi networks, or any others. It’ll stay off until you flip this particular switch back to the On position.
If, on the other hand, you use the one-touch switch that’s in Control Centre (see screenshot 1) – which on recent iPhone models is reached by swiping down from the top right – then you’re not really switching off Wi-Fi 2. Rather, you’re merely telling your iPhone to disconnect from all current known nearby networks.
Now, in most daily situations, this does have the same net effect as switching off Wi-Fi. However, importantly, it doesn’t actually switch off the Wi-Fi radio. Nor, incidentally, does it stop your iPhone trying 3 to make Wi-Fi connections in specific situations. These include walking or driving to a ‘new location’ (which could mean a just few yards up the street), or until 5am the next day, when Wi-Fi will automatically turn itself back on.
These subtle differences are explained on the Apple Support webpage, at , but few if any people would ever find that, and still less understand its implications.
