Apple’s much-anticipated product launch has finally arrived, and buried in the buzz about the waterproof iPhone 7 is the release date of WatchOS 3 software, available to anyone who owns a first-generation Apple Watch or buys the upcoming Apple Watch 2.
With the WatchOS 3 update, Apple Watches will be instantly equipped with a potentially life-saving SOS feature.
By pressing and holding the side button of your Apple Watch for six seconds, the wearer can initiate a crisis call to 911 or local emergency services across the globe.
Watch users will be placed on a live call with an emergency service, and, where available, their location will be automatically sent to the dispatcher. After the call concludes, a message containing a map to their location will be sent to anyone on the emergency contacts list.
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Any crucial medical information you opt to share in advance—allergies, age, blood type—will be displayed as part of a new Medical ID also enabled with WatchOS 3.
Notifications about location change will continue to be sent, and the Apple Watch (aapl) will continue to present health information for medical personnel, until the emergency is resolved.
You wouldn’t use this feature as often as you could be using Bluetooth headphones, and hopefully you’ll never use the SOS program at all. But if you’re traveling anywhere in the world, it’s the thing that may save your life in an emergency.
This story was originally published on TravelandLeisure.com.