Aside from the obvious, what are the wider use cases for this type of app?

Simple. Elegant. Does what it needs to do.
I tip my hat to you good sir.

How long should one configure the „absence“ time? I mean i dont want to click „I am alive“ daily. But also my Family would not want to wait half a year until they get access to our systems. Even 20days or so could be too small. Imagine you have an accident and are in the hospital „Intensivstation“ for this period. You are alive and will survive but cannot „check in“ and therefore the switch would fire

I have one set up to do several things for when it is my time, I made it fun and have a pop up box with questions, if you pass the questions it won’t activate.

I have hidden a treasure from my family fortune. A series of clues have been stored in various physical and digital forms around the world and the internet. The first clue will be sent using this web app.

The recipients will be a distribution list of my closest family, friends, and one of you reading this.

Reply here and I will determine a method to choose one you.

Let’s the mystery……begin!

Very impressive work

I know this is self hosted, but if you go away for a time, your infra will probably stop too, so this makes sense for a service rather than something you host.

I've thought about starting a service for this. Have the ability to send messages to different contacts through email, sms, or pre-recorded message.

I even thought about making a physical device that you could press, say every day, and it would send an API call to the service and realize you're still alive.

Is this something that people would actually consider paying for?