When Apple released iOS 10, the latest system software for the iPhone/iPad, it made a big deal out of the major features, like a redesigned Music app and contextual predictions in autocorrect.

But Apple’s engineer elves worked for a year to overhaul iOS 10, and they’ve planted lots of hidden gems. Today, I’m happy to present another of the best iOS 10 features that Apple forgot to mention.

This switch means “Let ringtones and vibrations play when this person calls or texts, even when Do Not Disturb is turned on.” A million parents will now get better sleep at night.

To find it, open Contacts; find the important person’s card; tap Edit; tap Ringtone. There’s the Emergency Bypass setting, right at the top.

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