Signal (intercom)

Absolutely minimal intercom system. Create a "Signal" or join someone else's, then use quick communication buttons in situations where it might be useful! Like, strictly hypothetically, when your wife yells up to you in your office that "TEA IS READY", and your dog starts barking until you come down - now, she can simply press the "TEA IS READY" button, you can respond with the "COMING" button, and no barking will ensue!