Sentinel automatically forwards your important messages and documents to your loved ones if you become unreachable for too long.
We always put off until tomorrow the message that truly matters: “I love you”, “I'm proud of you”, “here's where I kept everything”. Sentinel keeps watch so that, if life stops without warning, those words still reach the people we love.
“Dad, if you're reading these lines, it means I'm no longer here to say them. Know that every lesson you gave me shaped who I am. Thank you for everything. I love you.”
This is only an example. Your letter belongs to you, and you alone.
Your messages, documents and recipients, fully private.
A simple regular gesture confirms all is well.
Without a check-in, your messages are sent automatically to your loved ones.
Sentinel helps everyone protect their loved ones. Today, it is entirely free. Running the service (servers, sending emails) has a cost, and this cost grows with the number of users.
If the service grows, advanced options may one day become paid (a subscription) — always announced clearly and in advance. Your free support helps us keep the essentials accessible to as many people as possible, for as long as possible. 🙏
These last words should never come at a price. Your support helps us run Sentinel and keep access open to as many people as possible.
☕ DonateFree and voluntary donation. Today, no feature is paid.
Yes, it is entirely free today, with no paid feature. Since running costs grow with the number of users, we may in the future offer a subscription for advanced options — we will always let you know clearly and in advance. The project lives on voluntary donations from those who wish to.
You prepare your messages, documents and recipients. You regularly confirm your presence with a single gesture (a "check-in"). As long as you check in, nothing is sent. If you stop checking in, Sentinel sends you reminders, then — without a response within the delay you set — forwards your messages to your recipients.
You first receive an initial reminder, then a last reminder before the deadline. Without confirmation within the grace period you configured, Sentinel automatically forwards your messages and documents to your recipients.
Yes, everything is configurable: an interval in hours or days, or a calendar mode (fixed weekdays + time). You also set the length of the grace period and when the last reminder is sent.
Three modes to choose from. By default, the "secure link" mode: the email only contains a neutral notification + a link protected by email verification (the confidential content never travels through email). You can also send files as an encrypted ZIP archive, or as regular attachments.
Yes, for free. In Settings → Telegram, link your account in one gesture: you then receive your check-in reminders on Telegram with a one-tap button to confirm your presence, in addition to email.
Yes, optionally and in addition to email. From a recipient's card, you generate an invite link to send them; once they start the bot, they'll also receive on Telegram a secure notification to their message. The content stays protected by email verification.
Several safeguards: escalating reminders before any dispatch, a configurable grace period, a holiday (pause) mode, an optional "two-person rule" (a trusted contact must confirm your absence), and an anti-replay protection that cancels the dispatch if you check in at the last minute.
An optional safety: at the deadline, instead of sending directly, Sentinel first asks a trusted contact to confirm your absence. Without their confirmation within the delay you set, the dispatch happens automatically.
To ensure you actually own the address: such a sensitive tool must not be created with a wrong email. You receive a 6-digit code to enter once. It's also a protection against fake accounts and bots (reinforced by an anti-bot CAPTCHA).
Sentinel uses a primary sending provider and automatically switches to an independent second provider if it fails. On failure, delivery is retried several times automatically, and you're notified if a recipient could not be reached.
Yes: as long as your account is active, you receive a weekly health email (proof that automatic dispatch works) and an automatic monthly backup of your data (in JSON format).
Yes, a "Simulation (Dry Run)" button sends a sample of your messages to your own address, without sending anything to your recipients, so you can safely check everything.
Every security action (login, check-in, dispatch, deletion…) is timestamped and sealed with cryptographic hash-chaining: any attempt to modify or erase the history becomes immediately detectable. It's a guarantee of transparency and integrity.
Yes: your messages and files are encrypted at rest (AES-256) on our servers, passwords are hashed (never stored in plain text), communications are over HTTPS, and document access is protected by email verification. You can also lock the app with biometrics or a local PIN.
No, and we say it plainly: to be able to send your messages in your absence, the service must be able to decrypt them at send time. We never read your content and use it for no other purpose.
No one but your recipients, and only at the moment of triggering. Your content is neither sold nor used for advertising.
Yes: the holiday mode suspends monitoring while you're away, with automatic resume on the date you choose. No dispatch can occur during the pause.
Yes, at any time from the app (Settings → Delete my account) or from our website. To prevent accidental deletion, a double confirmation is required (typing the word "DELETE" + your password). Deletion is immediate and permanent.
The more people know, the more loved ones can be protected.