You've probably typed something into a chat window that you wouldn't say out loud in a waiting room. A hard week at work. A worry about someone you love that you haven't put into words for anyone yet. The line about not sleeping. The version of you that only shows up at 1am.
And somewhere right after you hit send, a quieter question shows up behind it: is it actually private to talk to an AI — or does this go somewhere you can't see?
So here's the plain answer, up front. With Seylen:
- Your words go to hardware we own. Seylen's AI runs on our own hardware — your conversations aren't sent to any third-party AI service.
- Your conversations are encrypted — in transit and at rest.
- No ads, no advertising trackers, and we don't sell your data.
- You can see everything Seylen remembers and delete any of it — item by item, or all at once by deleting your account.
That's the answer. The rest of this page is each piece in a little more detail — so you can weigh it for yourself instead of taking our word for it.
Where your words actually go: no third-party AI in the loop
Here's a part most people don't think to ask about: a lot of AI chat apps don't run their own AI at all. Your message leaves the app, travels out to a separate AI company's servers to get a reply, and comes back. Which means a company you've probably never heard of, whose policies you've probably never read, now has a copy of what you said — just to answer you.
Seylen doesn't work that way. Seylen's AI runs on our own hardware — your conversations aren't sent to any third-party AI service. When you write to Seylen, it's read and answered on servers we own and run ourselves. No outside AI company sits in that loop, quietly holding a copy of the conversation on its own servers, under its own rules.
That's not a small distinction. It's the difference between "trust us to handle this carefully" and "building from the ground up with privacy in mind."
AI chat privacy — "encrypted," decrypted
Your conversations with Seylen are encrypted — in transit and at rest. In transit means while your words are moving from your phone to our servers, they're travelling in a form that can't be casually read along the way. At rest means once they're stored, they stay stored encrypted — not sitting in a database as plain, readable text.
No ads. No trackers. A safeguard built to keep it that way.
There are no advertising trackers in Seylen. We don't sell your data, and we don't share it with advertisers. Nothing you say here becomes an ad profile of you, because there's no ad business on the other end of this app to build one for.
We also didn't want that to be the kind of promise that quietly stops being true a few releases from now — the sort of thing that slips in during a rushed sprint and nobody notices until it's already shipped. So it isn't only a policy. There's an automated check that runs against every single build of Seylen, and it fails on purpose — blocking the release outright — if anyone ever tries to add an ad tracker to the app. It's a rule the build system enforces, not just a line in a document somewhere.
What you can see, and what you can delete
Seylen remembers what you've shared with it, the way anyone who's been genuinely listening for a while would — so you don't have to start over every time you open the app. You can open what Seylen remembers, whenever you want, in "What Seylen remembers," and delete any of it. Deleting something removes it from what Seylen carries forward — though if you say the same thing again later, it can be noted again. When you delete your account, your data is removed from Seylen's live systems within a day. Our backups sit on our own hardware — never someone else's cloud — and are cleared after two weeks.
We keep your data until you decide to delete it. We don't quietly purge it on a schedule behind the scenes, and we're not going to pretend we do. What stays and what goes is genuinely yours to decide.
Where that leaves you
That's the same plain answer this page opened with — and nothing you have to take on a badge or a reassuring adjective. The full detail always lives in our Privacy Policy.
Seylen is a companion, not a therapist or counselor — built as a quiet place for otherwise healthy people navigating daily stress, somewhere to think out loud without wondering who else might be listening in.
Whenever you're ready, Seylen is here.
Seylen opens this fall.
Seylen is powered by AI. It is not a substitute for professional mental health care. If you are in crisis, please contact the 988 Suicide & Crisis Lifeline (call or text 988), text HOME to 741741, or call your local emergency number.