What Is a Dead Man's Switch?
A dead man's switch is a mechanism that acts on its own when the person in control stops responding. On a train, the driver holds down a lever; let go, and the brakes come on by themselves. Software swaps the hand for a check-in: you confirm you're fine on a schedule you set, and if you stop confirming, the switch does the thing you set it up to do. Sanctia is that, pointed at one job. Miss enough check-ins in a row and the letters, voice notes and photos you wrote in advance reach the people you named.
You have already used one
The handle you have to hold
Let go of a walk-behind mower's bar and the blade stops within seconds. Required by US law since the early 1980s.
The clip on your shirt
The cord you attach before you start. Come off the back and the belt stops without anyone having to notice.
The lanyard on your wrist
Same idea on the water. The machine assumes the worst the moment you are no longer holding on.
The handle it is named after
The dead man's handle, sometimes a pedal, has to be held for the train to keep moving. If the driver passes out, the grip goes and the brakes come on.
What happens when you miss one
Nothing, the first time. That is the part people get wrong about these things. A well built switch treats a missed check-in as a missed check-in, a dead battery or a week somewhere with no signal, not as proof you have died.
Several misses, not one
Sanctia waits for three consecutive misses by default. You choose the number, and a fresh reminder goes out at every step.
Answering is not a chore
Opening the app is a check-in by itself. Reminders arrive by email to start with; you can add push, or SMS once you have verified a phone number.
Then a hold
After the last missed check-in, Sanctia waits 24 hours by default before anything moves. You can make that longer.
The interval is yours. Anything from a day to a year, changed whenever you want.
One more layer exists and it is off until you ask for it. Trusted-contact confirmation puts a person in the way: before anything is delivered, someone you named is asked whether this is real, and they can stop it. Naming a trusted contact does not switch it on. And if you know you will be out of reach for surgery or a long trip, pause it instead. Planned silence should not have to look like the real thing. What happens if a switch sends by mistake works through the misfire cases in detail.
Who sets one up
Someone writing to one or two people
A letter. A voice recording. The context and instructions somebody will need if you die and are not there to explain any of it. That is the case Sanctia is built around. If it is yours, how to send a message after you die covers the options, including the ones that involve no app at all.
Someone holding a key for an heir
A password, a recovery phrase, a private key that is useless to your family if nobody can find it. In Sanctia that goes inside a passphrase-encrypted message, and the key is derived on your device, so nothing on our servers can open it.
A journalist or researcher with something to publish
A document set to release automatically if they go silent, as insurance against being detained. The same pattern turns up inside engineering teams, as a fallback that runs when nobody confirms a manual step by the deadline.
A family checking on someone who lives alone
At the plainest end, a way of making sure somebody gets told promptly when an isolated relative stops answering the phone.
Before you trust one
What happens if it fires by mistake
How many independent things have to go wrong before a delivery happens, and the one part nobody can undo afterwards.
How seven products compare
False alarms, whether a person can stop it, what you can send, encryption and platform, each read against the vendor's own published pages.
How to send a message after you die
A letter with your will, a scheduled email, a legacy contact, or a check-in app. Where each one falls short.
Sanctia is in early access. The web app is open to anyone today, the iPhone app comes through Apple's TestFlight, and Android is in open testing on Google Play.
Free during early access. No card, no phone number. Four minutes to set up, and you can delete your account whenever you want.