We all carry our phones everywhere—which means your device is a lifeline in the event of an emergency. Apple has a host of built-in features on iOS to facilitate getting help when it's needed, and you should take the time to turn on these critical settings on your iPhone (and know how to use them) before an emergency happens.

Adjust your Medical ID settings

If you're ever in an accident or experience an emergency in which you're unable to communicate, you will likely want first responders to have quick access to important medical information, such as allergies, medications, and health conditions. You can enter all of this into your Medical ID in the Health app and add a shortcut to your lock screen so responders can see it even if they can't unlock your device.

In the Health app, tap your profile picture and go to Medical ID. Add any relevant information about your health, including your blood type and any detailed notes. Toggle on Show When Locked—this will allow responders to pull up the information from your iPhone passcode screen via Emergency > Medical ID. You can also enable Share During Emergency Call, which will share your Medical ID if you call or text emergency services.

Add emergency contacts

While you're filling out your Medical ID, enter at least one emergency contact. Click Edit > Add Emergency Contact and select from your existing Contacts list. Tap the contact to add the relationship, such as a spouse or parent. There are also options for unrelated individuals like manager, teacher, social worker, or daycare. Your emergency contacts will be visible to first responders with your Medical ID. Your iPhone can also send a message to your contacts as part of Crash Detection and Emergency SOS, which we'll get into below.

Toggle Emergency Bypass on

If you're using Focus modes that silence notifications, you may still want to receive alerts from people you're close to in the event of an emergency—for example, your kid's school (or your actual kid). Emergency Bypass allows sounds and vibrations to break through even when your device is on silent. Emergency contacts in your Medical ID get this treatment by default, but you can enable it for others independently in their individual contact card. Tap Edit > Ringtone/Text Tone and toggle Emergency Bypass on.

Change settings for Emergency SOS

Emergency SOS is a long-standing iPhone feature that allows you to quickly call or text emergency services (and, if you're in the U.S., share your Medical ID when doing so). You don't specifically need to enable it, but you can change the mechanism for initiating the call under Settings > Emergency SOS and switch the toggle next to Call with Hold and Release and/or Call with 5 Button Presses. You can also initiate an emergency call from your iPhone passcode screen and text emergency services from Messages.

You can also use Emergency SOS via satellite if you're out of service. This newer feature connects you to the closest first responders wherever you are, and it is only available when there's no cellular or wifi connection. If your call won't connect, tap Emergency Text via Satellite > Report Emergency and follow the prompts. Your device will send information to responders, such as your location, remaining iPhone battery life, and Medical ID. Ensure location sharing for Emergency Calls & SOS is on under Settings > Privacy & Security > Location Services > System Services. For the time being, Emergency SOS via satellite is free, though it's not available worldwide. Satellite is also available for requesting roadside assistance in the U.S., UK, and Australia.

Turn on Crash Detection

Crash Detection is an iPhone and Apple Watch feature that can call emergency services and alert your emergency contacts if your vehicle has been in a severe crash, such as a collision or rollover. You'll hear an alarm and get a display alert on your device with an emergency call slider, and you can either complete the call or dismiss the alert if you don't need emergency services. If you don't do either within 10 seconds, your device will automatically make the call after another 30-second countdown. It will also send your location to your emergency contacts and display a Medical ID slider for emergency responders, which is why it's important to set both of these up. Crash detection is on by default, but you can turn it off under Settings > Emergency SOS.

Make sure your emergency alerts are active

Your iPhone can also notify you when there are safety issues, extreme weather, or other critical incidents in your area. You don't actually need to turn these on, as government alerts—public safety, emergency, and AMBER—are enabled by default, but you should ensure yours are active under Settings > Notifications (scroll all the way to the bottom). Click into the Enhance Safety Alerts menu for additional settings for earthquake and "imminent threat" alerts, which may include supplemental alerts for floods and other natural disasters.