Kard Kulture

Privacy Policy

Last updated: 12 October 2026

The short version

Your Kards, your decks and your entire study history are stored on your own device. Kard Kulture runs as an iPhone app and in a web browser, and the same rules apply in both.

When you ask Kard Kulture to make something — import a document, build a test, write a memory aid, ask the Tutor — the material that request needs is sent to our service and on to our AI provider, because that is the only way to generate it.

If you sign in, a copy of your study data is also stored in our own cloud service so your other devices can have it. That is the only thing an account changes, it is described in full under Accounts below, and the documents you imported are not part of it.

An account is optional and most of this app never needs one. If you create one, we hold an opaque account identifier and the sign-in methods attached to it — see Accounts below. Without one we never ask for your name, your email or your phone number, and we could not identify you from what we hold.

What stays on your device

• Every Kard, deck, chapter and tag.
• Your whole review history and scheduling state — what you got right, what you got wrong, and when each card is next due.
• Your settings, including your chosen app colour and Kard style.
• Copies of the documents you import, kept so a Kard’s citation can open the page it came from.

Without an account, none of this is uploaded, backed up to us, or readable by us. It lives in the app’s own storage on the device and goes when the app goes.

With an account, everything in that list except the imported documents is also stored in our cloud service, so your other devices can have it — see Accounts. The documents stay on the device that imported them either way.

What is sent, and when

This section is about generating — the moments your material is sent to an AI provider. They are listed here in full, and they are the same with or without an account.

Signing in sends study data for a different reason and to a different place: to our own cloud service, so your devices agree with each other. Nothing in that path reaches an AI provider, and it is described under Accounts.

Import a PDF, a photo or pasted text

The document itself

Check an imported lecture for a newer version

The new version of the document, so the two can be compared

Use Test me

The front and back text of the Kards being tested, up to sixty at a time

Get a wrong answer explained

That question, its options, the answer you gave, the correct answer, and the passages the question came from

Ask the Tutor

The front and back text of that Kard, the title of the lecture it is in, the passages behind it, the names of the ideas it is about, and two counts — how many separate occasions this idea has been missed on, across how many cards

Build a course’s concept map

The passages of that course’s lectures, and the front and back text of its Kards

Confirm a link between two ideas

The names of the two ideas, short quotes from the passages behind each, and the Kards involved

Use Remember this

The front and back text of that one Kard

Each request carries an opaque install identifier: a random value created the first time the app runs and kept in the device keychain. It is not an account, not an email and not a device fingerprint; nothing else is derived from it. We use it only to count usage against your plan’s allowance.

We do not send your review history, your scheduling data, your settings, or any Kard you are not actively asking us to work on to an AI provider. The Tutor is the one place a number derived from your history is sent, and it is two counts about one idea — never a conclusion about you, and never the reviews themselves. Your review history does reach our own cloud service if you have an account, which is a different thing and is described under Accounts.

Lecture titles are sent only with a Tutor request, where they tell the model what the material is about. No other request carries a deck, chapter or course name.

Who processes it

Requests are handled by the Kard Kulture service and passed to OpenAI or Anthropic, which perform the generation. Which of the two handles a given request is decided by the Kard Kulture service, not by you, and can differ from one import to the next. Each handles the data under its own terms as a service provider to us.

Your material is not used by us to train any model, and we have not agreed to any arrangement that would allow it to be used for training by our providers.

How long we keep it

• Documents staged for import: deleted automatically ten minutes after upload. The clock is fixed and is never extended.
• Import records (progress, counts, and the generated Kards until your device collects them — for a long import's job and for a short import's single request alike): deleted automatically two hours after the import is started.
• Text sent for Test me, the Tutor, a wrong-answer explanation, a concept map or Remember this: held only for the lifetime of the request. It is not written to storage.
• Documents sent to compare two versions of a lecture: the same ten-minute staging window as an import, and the comparison itself keeps only a fingerprint of each page, never its text.

After those windows we hold nothing that came from your device except the opaque install identifier, a record of how much of your allowance you have used, and — if you made one — your account identifier, the installations attached to it, and the synced copy of your study data described under Accounts. That copy is kept for as long as the account exists, because its whole purpose is to still be there when you set up your next device.

We do not log the contents of your documents or your Kards. Server logs record the shape of a request — which endpoint, whether it succeeded, how long it took, how many Kards it produced — and never the study material itself.

The early-access list

Everything above is about the app. Joining the early-access list is a separate thing you choose to do on this website, so it is written out separately. If you have not joined it, none of this applies to you.

• What we store: your email address, the exact wording of the consent you agreed to and the moment you agreed to it, whether you have confirmed the address, and the campaign parameters that were in the link you arrived through — which tells us a community found us, not who you are.
• Your IP address: never stored. A one-way hash of it is held so one machine cannot sign up a thousand addresses, and those rows are deleted once they are more than a day old.
• Why: to confirm the address is yours, and to email you when Kard Kulture is ready. The basis is your consent, and you can withdraw it at any time.
• Who else sees it: Hetzner, who host the server this list lives on, in Finland; and Resend, who deliver the email. Nobody else. We do not sell it, and we do not use it to advertise to you anywhere else.

The confirmation email contains no tracking pixel and no rewritten links. We do not record whether you opened it.

How long: we have not set an automatic deletion schedule for this list, and we would rather say so than print a period we do not actually enforce. What is certain is that the unsubscribe link in every email deletes your record immediately — not a flag, the row — leaving only an anonymous count. You can also write to us and ask.

Analytics

The app sends no analytics. It contains an event system that records only counts, durations and settings values, with a guard that strips anything carrying study content — but in the shipping build nothing is connected to it, so nothing is recorded and nothing is transmitted.

This website sends none either. It has no cookies, no trackers and no third-party scripts of any kind.

Payments

Subscriptions are sold through Apple. Apple handles the payment; we never see your card details. RevenueCat verifies the purchase on our behalf and tells the app whether a subscription is active. What they hold is governed by their own privacy policy.

Accounts

An account is optional. Kard Kulture works completely without one: you can make Kards, import documents, study and review, and nothing asks you to sign in. An account exists so that your plan and your allowance stay with you when you replace a device or reinstall.

If you create one, you sign in with Sign in with Apple or with a link sent to your email address. There is no password. Sign-in is handled by Firebase Authentication, a Google service, which verifies who you are and issues the session your device uses. What they hold is governed by their own privacy policy.

What we hold for an account is an opaque account identifier, the sign-in methods attached to it, and a record of which installations belong to it — so that the allowance you have already used stays yours and does not start again. If you sign in with Apple and choose to hide your address, Apple gives us a relay address; that is normal and we treat it the same way. Your email address is never the thing that identifies your account.

Your library follows your account. When you are signed in, Kard Kulture stores a copy of your study data in its own cloud service so your other devices can have it too. What is stored is:

• your decks, chapters and courses, and the names you gave them;
• your Kards, in full — their questions, answers, memory aids and tags;
• your review history: what you rated, when, and how long you spent;
• your exams and exam plans;
• your Test me results — what you got right and wrong, but not what you typed;
• the passages behind your Kards, with the page and the document they came from, so a citation can be checked on any of your devices;
• the settings that are about studying: your Kard style, your daily target, your app colour.

Your original documents are not stored in the cloud. The PDFs, photographs and Anki files you import stay on the device you imported them on. A second device shows the Kards and the passage behind each one, and says plainly that the original file is elsewhere. We do not back your documents up, and you should not treat Kard Kulture as a place they are kept.

Tutor answers are not stored in the cloud either. They are cached on the device that asked, and another device produces a fresh answer from the passages that did travel.

Some things are deliberately left on the device they belong to: whether this device may send you notifications, whether it has haptics, your search index, and the scheduling itself — which is recalculated on each device from your review history rather than copied, so two devices cannot disagree about when a Kard is due.

Without an account, none of this happens. An anonymous library is stored on its device and nowhere else, and everything in the app works that way.

We do not claim end-to-end encryption. Your study data travels over an encrypted connection and is held in an encrypted database by our infrastructure provider; it is readable by the Kard Kulture service, which is what makes it possible to serve back to your other devices. It is not used to train any model, it is not sold, and it is not shared with anyone beyond the providers named on this page.

You can delete your account from inside the app, at any time. Deleting it removes your Kard Kulture account, deletes the cloud copy of your study data, and signs you out. It does not delete the Kards on your device — Delete everything below does that — and it does not cancel an App Store subscription, which is managed in your Apple ID settings.

When you delete an account we remove the link between it and the devices that belonged to it, and the record of how much of your allowance you had used moves back to the opaque install identifier it was counted under before. We keep that record, because an account deletion is not a way to start a new free allowance; we do not keep anything that says which device belonged to you. The account identifier itself is retained as a marker that it was deleted, so that a sign-in issued before the deletion stops working.

We hold no profile of you. There is no name, no photograph, no address book and nothing about what you study — an account is a way to prove the plan is yours, and nothing more.

Your control

• Export. Settings → Export my Kards produces a file of everything you have made. It is created on your device and goes nowhere until you send it somewhere.
• Delete. Settings → Delete everything removes every deck, Kard, review, exam, import record and retained document from the device, and stops this device syncing. Without an account we store nothing on our side that is tied to you beyond the retention windows above, so that alone is a complete deletion. With one, the cloud copy is removed by Delete account — the two are separate actions because they do separate things, and either can be done without the other.
• You can stop sending anything at any time simply by not using the features that generate. Everything you have already made keeps working offline.

Children

Kard Kulture is not directed at children under 13 and we do not knowingly collect anything from them. We hold no information that would let us identify anyone’s age.

Changes

If this policy changes, the updated version will be published at this address with a new “last updated” date. Material changes will be surfaced in the app.

Contact

Questions about this policy, or about anything the app does with your material: support@kelterstudio.com.