Cardlet — Privacy Policy
Last updated: 8 September 2026
This policy takes effect when Cardlet is first released on the App Store.
Cardlet is a study app: you write notes, it turns them into flashcards, and it schedules your reviews. This policy explains what it stores, where, and why.
The short version: Cardlet works on your device without an account or a paid plan. Signing in lets you buy or restore a plan. Cardlet Pro adds sync between your devices, and Cardlet Pro + AI also adds cloud AI. Nothing is sold, nothing is shared with advertisers, and there is no analytics or tracking of any kind.
1. Who is responsible
Vladislav Morozovskii (“we”) operates Cardlet and the servers behind it.
Contact for any privacy question, request or complaint: vladmorozovskii@icloud.com
2. If you never sign in
Cardlet is usable without an account. In that case:
- Your notes, flashcards, decks, planner, exams and study statistics are stored only on your device, in the app’s own storage.
- Flashcard generation runs on your device using Apple’s on-device model, or a built-in text analysis when that model is unavailable. Your text does not leave the device.
- We receive nothing. We do not know the app is installed.
Two exceptions, both of which happen only when you ask for them:
- YouTube links. If you paste a YouTube link, the app asks YouTube for the video’s title. That request goes to Google, not to us, and is subject to Google’s privacy policy.
- Files you import or export. These stay on your device or go wherever you send them through the iOS share sheet.
3. If you sign in
Signing in uses Sign in with Apple. There is no password and we never see one.
What we receive and store
| Data | Why | Kept for |
|---|---|---|
| Apple user identifier | Identifies your account. It is specific to Cardlet — it is not your Apple ID | Until you delete your account |
| Name and email address, if you choose to share them | Shown on your profile screen | Until you delete your account |
| Apple refresh token | Required so that deleting your account also revokes Cardlet’s access to your Apple ID | Until you delete your account |
| Your document: notes, flashcards, decks, planner items, exams, study history, if you have an active sync plan | Sync between your devices | Until you delete it or your account |
| The last 20 previous versions of that synced document | So a bad sync or a mistaken overwrite can be undone | Replaced as newer versions arrive |
| Images you attach to synced notes | Sync between your devices | While a note or a retained version still refers to them |
| Sign-in session tokens | Keeps you signed in | Sessions expire after 90 days of no use |
Apple may give you a private relay email address instead of your real one. If so, that is all we ever have.
What we do not store
- Passwords — there are none.
- Payment details — see §5.
- Location, contacts, calendars, photos beyond the images you attach, health data, or any device identifier for advertising.
- Any advertising profile or analytics event. The app contains no analytics SDK, advertising SDK, crash-reporting SDK or third-party tracker. Operational and AI allowance records are described in sections 4 and 6.
4. Cloud AI
Cloud flashcard generation requires Cardlet Pro + AI and is off until you turn it on, on a screen that names the provider and explains what is sent. You can withdraw that consent at any time in the app, and generation returns to the on-device model.
When it is on and you generate cards:
- The text you asked to turn into cards — pasted text, extracted PDF text, a recording’s transcript, or a topic — is sent to our server and forwarded to OpenRouter (openrouter.ai), which routes it to the model that produces the cards.
- We do not store that text and we do not log it. It exists in memory for the duration of the request. What we keep is metadata only: which kind of source it was, how many characters it contained, how many cards came back, which model answered, how long it took, and whether it failed. That record is what counts your monthly allowance.
- OpenRouter and the model provider it routes to process the text under their own terms: openrouter.ai/privacy. Please read it before turning cloud AI on. If you would rather no text ever left your device, leave it off — the app works without it.
- Do not paste material you are not free to share with a third party.
Your monthly allowance is counted per calendar month in UTC and resets on the 1st.
5. Subscriptions
Cardlet Pro and Cardlet Pro + AI are sold through Apple’s In-App Purchase. Apple handles the payment. We never see your card, bank details or billing address.
From Apple we receive and store: the product you bought, Apple’s durable transaction identifier for that subscription, its status, its expiry date, whether it is set to auto-renew, and whether it is a production or sandbox purchase. We need these to know which plan features to unlock. They are kept while your account exists.
Apple’s own handling of the transaction is covered by Apple’s privacy policy.
6. Server logs
Our server keeps operational logs to run the service and investigate problems. They contain the request path, response status, timing, and the IP address the request came from. AI allowance records also contain the source type, character and card counts, model, latency and error code. These records are linked to the account so we can enforce allowances and investigate failures. They do not contain note text, flashcard text, images, audio, or anything you typed. Logs rotate automatically and older ones are discarded.
7. Where your data is
On our own server, hosted at hiphosting in Poland. It is not shared with any other company except as described in §4 (OpenRouter, only with your consent) and §5 (Apple, for purchases).
Backups of the database and image storage are taken daily on the same server and kept for 14 days. Deleting your account removes your data from the live service immediately; backup copies age out on that schedule.
8. Deleting your account
Profile → Delete account, inside the app.
It removes your document and all retained versions, your images, your sign-in sessions, your AI usage records and your profile — immediately and permanently. It also revokes Cardlet’s Sign in with Apple grant.
It does not cancel your subscription. Apple owns that relationship, and only you can cancel it: Settings → your name → Subscriptions, or apps.apple.com/account/subscriptions. The app tells you this before it deletes anything. If you delete your account without cancelling, Apple will keep billing you.
Data on your device is removed by deleting the app.
9. Your rights
You can, at any time:
- See and export your data — it is all in the app; notes export as text or PDF, decks export in a format Anki and Quizlet accept.
- Delete it — see §8.
- Withdraw consent for cloud AI — see §4.
- Ask us anything about the above, or complain, at vladmorozovskii@icloud.com. We answer within 30 days.
If you are in the EU or the UK, our legal basis is: performing our contract with you (your account, sync and subscription), your consent (cloud AI), and our legitimate interest in keeping the service running and secure (server logs, backups, abuse prevention). You have the right to lodge a complaint with your national data protection authority.
10. Children
Cardlet is not directed at children under 13, and we do not knowingly collect data from them. If you believe a child has given us data, write to vladmorozovskii@icloud.com and we will delete it.
11. Changes
If this policy changes in a way that affects you, the app will tell you before the change takes effect, and — if the change concerns cloud AI — will ask for your consent again rather than assuming the old one still applies.