iOS 11 brought many excellent new features to iPhone and iPad when it launched in autumn 2017. Among these was a clever shortcut that allows users to make a call to the emergency services just by pressing a single button. It's called SOS mode, and we show you how you can use it on your iPhone today.
As SOS mode is an iOS 11 feature, you'll need to be running iOS or later to access it.
iOS is available for the iPhone 5s and later. If you've got an older iPhone, then we're afraid you cannot get iOS, and therefore you cannot get SOS mode either. (If you decide to upgrade to a newer model, take a look at our iPhone buying guide and our roundup of the best iPhone deals.)
Setting up SOS mode
With iOS 11 on your device, go to Settings and scroll down until you see the new Emergency SOS section. (It's just below Touch ID & Passcode.) Tap on this and you'll be presented with an animation that shows how the feature is used on your handset.
The default method on an iPhone 8 Plus is to "press and keep holding the side button and either volume button to make an emergency call", but if you select the Call with Side Button option you can choose to place the call by rapidly pressing the side button five times.
To enable SOS mode, slide the Auto Call button to the right so it turns green.
Scroll down a little more and you'll see the option to 'Set up Emergency Contacts in Health'. You don't need to do this for SOS to work, but if you do, they will automatically be sent messages if you use the Emergency SOS feature.
The final option at the bottom of the page is for a Countdown Sound. As the name suggests, this will warn you audibly that the SOS mode has been activated and is about to contact the emergency services.
The countdown sound is there so you can know the feature is working if you're not able to see the screen, or to cancel the call if triggered by accident.
Using SOS mode
Obviously, it's a good idea to test out the SOS mode before your life depends on it. You can do this without actually calling the emergency services; you just have to be quick.
If you have the Countdown Sound enabled, then you might get a bit of a shock, not to mention a fair few stares in public places, as the klaxon sound it produces is quite loud. So it might be best to disable it while you test the system.
Now all you need to do is press the power button five times in quick succession (or whatever your chosen activation method is), even if the phone is locked. A countdown will appear on the screen, starting at three. Press the Stop button underneath, then confirm this by pressing the Stop Calling option that immediately appears.
Note that as well as letting you easily contact the emergency services, SOS mode also disables the Touch ID fingerprint scanner on your iPhone. This is handy if you're being mugged or arrested and don't want to be compelled to unlock your device.
If you press the power/side button five times to bring up the emergency services option and then press cancel - or indeed if you go ahead and call the emergency services from that screen - then iOS will automatically lock Touch ID so that it cannot be used to open the phone. You (or the cop confiscating your device) will need to enter a passcode to unlock it, after which Touch ID will work normally.
There you are. Now if you ever find yourself in a dangerous situation, and we sincerely hope that isn't the case, then you have a quick way to call for help.
On a related note, let's briefly discuss Advanced Mobile Location, or AML, which Apple has said will be arriving on iPhone with the iOS 11.3 update, in beta at time of writing and expected to roll out to the general public in spring 2018.
AML is a standardised technology that is used by smartphones by many manufacturers to quickly give your location to the emergency services, and can therefore save the day in a crisis much like SOS mode. (You can read more about AML here.) But while Google incorporated AML into Android phones back in 2016, Apple held back.
We don't know why. But we do know that Apple is coming round to the idea, which means that, after the benefits of SOS mode in iOS 11.0, we will soon be getting AML in iOS 11.3.