iOS: iOS 10 adds a new feature to contacts called Emergency Bypass. With this setting, you can make it so that any time a specific contact tries to get in touch with you your phone will make a sound. First off: Emergency Bypass goes through both Do Not Disturb mode and your phone's silent switch, so you'll only want to use this for potential big deal emergencies. You can also set it up for the phone ringtone or text messaging exclusively, which is handy if you have someone who only calls when its an emergency. Here's how to set it up:
- Launch Contacts.
- Tap the contact you want and then tap Edit.
- Tap Ringtone (or tap Text Tone if you want texts to go through).
- Set the Emergency Bypass toggle to On.
Now, calls or texts (or both) will get through from that contact no matter what.