These smartphone settings could save your life

Emergencies are, by definition, unexpected, so it’s critical to know exactly how your phone can help when you need it most. Both iOS and Android have safety features that will almost instantly alert first responders, family, and friends to the fact that you need assistance.

If you fear pocket-dialing the paramedics, you can limit these settings, but you can’t shut them off entirely—federal law requires all phones sold in the US to be able to dial 911, whether or not they have an active SIM card or are linked to the available wireless networks. As long as your device can make some sort of connection, you should be able to call for aid.

By default, an iPhone 8 or later model will call for help if you hold down the side button and either volume button. Do this, and the Emergency SOS slider will appear within seconds. Then, you can drag it to the right to make the call or keep holding to activate a 10-second countdown before the call goes out. You can turn this off by going to the Settings app, then Emergency SOS, and toggling off the switch next to Call with Hold and Release. During the countdown, your phone will vibrate to let you know it’s working. Stop the countdown at any time by releasing the buttons, but know that if you release the buttons after the countdown ends, your phone will call emergency services.

On all iPhone models, you can rapidly press the side or top button five times to do the same thing (except in India, where it’s three times). While this setting is the default on any iPhone 7 or earlier model, you can turn it off on newer devices by opening the Settings app, finding Emergency SOS, and toggling off the Call with Side Button switch. If you do use it, you have to press it quickly or it won’t work. This method starts an eight-second countdown before the call goes out, and will activate a loud alarm even if your phone volume is completely off. The only way to prevent the siren is to toggle on the Call Quietly switch within the Emergency SOS settings. Cancel a call by tapping the Stop button and confirming that you want to Stop Calling.

There used to be an “auto call” toggle switch within the Emergency SOS settings, but this appears to have disappeared in newer versions of iOS. Now that it’s permanently active, your phone will automatically dial the local emergency number once its countdown ends or as otherwise described above. This feature also requires a SIM card and you might still need to specify an emergency service in some areas, Apple says.

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You can manage your emergency contacts within the Emergency SOS settings by tapping Edit Emergency Contacts in Health, which will take you to Apple’s built-in Health app. There, hit Edit in the top right and scroll down to add emergency contact. After any emergency call ends, your phone will text these contacts about your situation unless you choose to cancel the message. Your device will also send them your location and update them when your location changes, even if location services are off.

If you’ve set a lock screen on your device, the passcode entry screen will have an emergency call button at the bottom. You or anyone else will be able to dial 911 from this screen, whether it does so automatically or requires you to plug in the number manually.

Your phone will also send your location to first responders during an emergency call or text if you have Android Emergency Location Service on and it’s available in the country you’re in. You can also set this tool up to notify previously selected emergency contacts that you’re in distress. If you do this, your phone will send them text messages with your location and whether or not you’ve been in contact with emergency services. To manage this feature, open Settings and tap Location, followed by Location Services. Go to Emergency Location Service and toggle the switch on the next screen to turn it on or off. 

The safety features on your Android also include Earthquake Alerts, which you’ll be able to turn on from the Emergency Location Service menu. This tool uses information from ShakeAlert in California, Oregon, and Washington, as well as other Android devices across the globe to tell you when the earth is moving under you. Whenever a quake registering 4.5 or above on the Richter scale happens, your device will let you know the approximate intensity, how far you are from the epicenter, and give you tips on what to do to stay safe.