The Apple Watch can track your heart rate, monitor your steps and calories burned. In a future version it may also be able to call out when you’re in need of urgent care.

A patent application titled “Care Event Detection and Alerts” was published Thursday by the U.S. Patent Trademark Office, revealing a new invention from Apple which would use the sensors of an Apple Watch or another device with health-tracking features to send out alerts when the wearer is in need of help or medical assistance. Apple refers to this occurences as “care events” in the patent and suggests it could be used in the event of a car crash, bike accident, heart attack, separation of a child from caregiver, mugging or more.

In one version of the patent, after detecting an emergency event, the Apple Watch could tailor its emergency alert based on the severity of the wearer’s condition. For instance if an emergency occurred, the watch could send out an alert to immediate family members, such as the case of an elderly person falling over. But if the watch doesn’t detect a heartbeat, it can skip the first tier alert contacts and go straight to calling emergency services via 911 or other local emergency contact numbers.

Apple Watch 2 Alert Invention A composite of illustrations and flowcharts detailing Apple's emergency alert invention. Photo: USPTO/Apple Inc.

Since the Apple Watch doesn’t have a cellular radio of its own, Apple could use a paired iPhone’s mobile data connection to send out the alert as well. In another version of the invention, the watch could also send out alerts via a "mesh network," by connecting to a nearby device. If no means of communication is available via phone or wireless data, the alert system could also default to sending a SOS alert via a GPS device signal.

As with many of Apple’s patent applications, it’s unknown if or when it plans to use the feature in one of its devices. Apple filed the patent application on Sept. 9, 2015 and credits Apple engineers Martha Hankey and James Foster for the invention.

Apple's first smartwatch went on sale on Apr. 24, 2015. While Apple hasn't officially said a new Apple Watch is in the works, a fully redesigned model could hit the stage in the second half of 2016, according to 9to5Mac.