Dead Man's Switch

A check-in app for iPhone. If you go quiet, the people you chose are told.

Pick how often you'll check in: every day by a set time, every few days, or anything up to once a year. Check in with one tap. If you miss your deadline, your phone reminds you first. If you still don't check in, the people you chose get the email you wrote, and they hear from you again the moment you check in.

People use it when they live alone, hike or travel on their own, have a health condition, or just want someone to notice if a few days go by.

Free on iPhone, with an Apple Watch app. Pro is optional. No account needed.

Home: 1 day, 13:41:58 left, check in by Sat 1:38 AM, a timeline showing when contacts are emailed, and a round Check in button — No check-in? Your people are told.

The message screen: a name, a message about a hike, buttons to add an address, spare key, health notes or who to call, and a preview of the exact alert email — Your words, to the people you choose.

The Lock Screen: Check in soon, 6:11:22 left, contacts emailed at Sat 12:41 AM if you miss it, and a Check in button — Check in from your Lock Screen.

Right after checking in: 1 day, 23:59:22 left and Confirmed by the server at 11:56:18 AM — One tap, confirmed by the server.

Check in every: every day by 9:00 PM is chosen, contacts emailed 6 hours after a miss; below it rolling clocks from every day to custom, and a Short safety timer card marked Pro — Every day by the same time.

You missed your deadline: 07:35:58 until Jamie, Sam and Mom are emailed at 7:33 PM, with a red I'm OK button — Miss it? You hear first.

An alarm screen: Check in before 4:54 PM, a large Check In button and slide to stop — Still quiet? Your phone rings.

Away: a calendar with Tuesday, November 3 picked and You're away until Tue, Nov 3 at 6:00 PM — Off the grid? Say when you're back.

Safety timer: back by 2:17 PM, 3 hours, a note saying Bear Mountain loop, parked at the north lot, and I'm back and Add an hour buttons — Out for a hike? Set a safety timer.

The Apple Watch app: Checked in, 37:41:58 left, by Mon 2:32 AM, and a Check in button — Check in from your wrist.

Real screenshots of the app with sample contacts.

How it works

Check in with one tap: in the app, from a widget, a notification, Siri, Control Center, the Action Button, your Lock Screen or your Apple Watch
Or let it happen: a Shortcuts automation can check you in when you stop your morning alarm
Every check-in is confirmed by our server, and a live countdown shows how long you have
Reminders before your deadline, then a grace period before anyone is emailed
An hour before anyone is told, your phone can ring like an alarm clock, even on silent (iOS 26)
Write one message for everyone or a personal one for each person, and add what they'd need: your address, where the spare key is, health notes, who to call
The people you add get a short heads-up email, and you can send them a test any time, so a real alert is never a surprise
Alert emails have an "I'm checking on them" button, so you can see when someone is on it
Going somewhere without signal? Set Away until the day you're back
In English, Spanish, German, Polish, French, Italian, Dutch, Japanese and Korean, with alert emails in your language (Korean emails go out in English for now)
In the US and Canada, the people you add can also get a text, once they say yes themselves (SMS terms). Texts come in small packs; emails are always free

Free, with an optional Pro

Everything above is free, for up to 3 people. Pro adds a safety timer for a hike, a run, a first date or a long drive (a few hours, with a note of where you went), up to 10 people, and extra app icons.

Pro is $9.99 a year (the first week is free), $1.99 a month, or $19.99 once. These are US prices; the app shows yours. Subscriptions renew until you cancel them in your Apple Account settings.

Privacy

No account, no location tracking, no ads. The only personal data is the people you add and the message you write: our server keeps them to send your alerts and deletes them when you turn the switch off. New installs count which setup steps they reach, as anonymous daily totals with nothing about you. Privacy policy

Support

Questions, feedback, or want your data deleted? hello@tomorrowish.dev, or see support.

Dead Man's Switch is not an emergency service and does not contact emergency services. If you are in danger, call 911 or your local emergency number.