The website gives you the chat. The Windows app gives you everything the chat produces — history, notes, calendar, tasks, projects — and the reason for that split is not a missing feature. It is where the key lives.
Why the site cannot show your history
Your conversations are encrypted before they are stored. The key that opens them is handed out only to a client that can prove which device it is: the phone apps prove it with an attestation token from the platform, and the desktop app proves it with a signature from a key it generated on first run and keeps in the machine’s own keychain. The private half never leaves the computer.
A browser tab cannot make that proof, and this is deliberate rather than unfinished. Anything that can run script in the page could ask for the key too — so the answer is that the page is never given one. The consequence is honest and visible: on the website you get the chat, and your library lives in the apps.
The site is not missing your history. It is not allowed to open it.
What the Windows app adds
- •History. Every conversation, searchable, and the same conversations your phone shows.
- •Notes, tasks and projects. Written on the PC, readable on the phone, encrypted in both directions.
- •Today and calendar. The day’s events and reminders in the same place as the assistant that can act on them.
- •Files and pictures. Attach a PDF or an image and ask about it. The text is what reaches the model.
- •Updates that arrive on their own. The app checks for a new version and installs it, so a fix reaches you without a visit to a download page.
Installing it
One file from the download page, signed as Secure Artificial Intelligence, Inc. Windows verifies that signature before running the installer — which is the check worth caring about on any download, not only this one: it says the file came from the named company and has not been modified on the way to you.
The install is per-user and takes a few seconds. There is no account step: the app opens as a guest, and signing in is what links this PC to the library on your phone.
Questions
Does it work offline?
The interface is on your machine rather than fetched from a website, so the app opens and your existing notes and conversations are there without a connection. Asking a question needs one, because that is a request to a model.
Is my data stored on the PC or in the account?
Both, and that is what makes the phone and the PC show the same library. What is kept in the account is encrypted, and what the model provider is told about you is covered in what a model never sees.
Is there a Mac version?
Yes — the same app, on the same download page, which offers the build that matches the machine you are reading this on.
Try Secure AI free
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