The exit call: tap your phone twice, get a real call a minute later.

Why a real call

There are plenty of "fake call" apps. They draw a picture of an incoming call on your screen. It works until someone is close enough to see the screen, or your watch doesn't buzz, or the car doesn't ring, or you have to unlock the phone to start it, which is the one thing you can't do discreetly. I wanted the real thing: a call that comes in over the phone network, rings on the watch and in the car, shows a caller name on the lock screen, and can be triggered with the phone face-down in my pocket.

The trick is that the phone can send a text without you looking at it, and a text can trigger anything. The rest is plumbing.

How it works

• The trigger. iPhone's Back Tap (Settings → Accessibility → Touch → Back Tap) runs a Shortcut on a double or triple tap of the phone's back. The Shortcut is one action: send a text with a fixed word to a number.
• The number. A Twilio phone number, about $1.15 a month. When it receives a text, Twilio posts the message to a URL I set.
• The webhook. A few lines on a server (a free-tier function works): read who texted, wait a random 30–60 seconds, then ask Twilio to place a call from the number to that phone. When the call connects, Twilio plays a short recording so there's a voice on the line if anyone is listening.
• The contact. The Twilio number is saved in my phone as Emergency. That's what shows on the lock screen, the watch and the car.

Two taps, pocket the phone, keep talking. A minute later: an emergency. I've used it at work and outside of it, and it has worked every time I needed it.

What I learned using it

• The delay sells it. A call that arrives the instant you touch your phone looks staged. 30–60 seconds, randomized, looks like life.
• Answer it. A declined "emergency" call is less convincing than a ten-second "yeah — okay — I'm on my way." The recording on the line gives you something to react to.
• Back Tap is the weak link. It misses sometimes, especially through a thick case, and triple-tap is more reliable than double but harder to do casually. On an iPhone 15 Pro or newer, the Action Button is a better trigger: one press, no ambiguity. An Apple Watch complication works too.
• It's cheap enough to forget about. The number costs about a dollar a month and each call about a cent a minute. Twilio bills a prepaid balance; $20 covered setup and lasts a long time.
• Keep the keyword simple. Any text to the number triggers the call. I use one word. A number in the text could set the delay in minutes if you want a scheduled exit instead of an immediate one.

Build it yourself

The full thing is simpler than this page. In order:

• Create a Twilio account, buy a local number, and put $20 on the balance.
• Deploy a webhook that does two things: on an incoming SMS, schedule a call back to the sender after a short delay; on the call connecting, play a short message. Twilio's own docs cover both halves ("respond to an incoming SMS" and "make an outbound call") and either half is under 20 lines in any language. Point the number's messaging webhook at it.
• Save the number as a contact named whatever would make you leave a room.
• Make a Shortcut with one action — Send Message, your keyword, to that contact — and assign it to Back Tap or the Action Button.
• Test it with the phone in your pocket, not in your hand.

That's the whole build. It's the kind of thing anyone could have made, and I'm a little surprised more people haven't.

Not for sale, no app, nothing to sign up for; it's a recipe. Questions: Discord.