Privacy Policy
Last updated 20 August 2026
The short version: Curio has no accounts, no trackers, no advertising and no analytics. What you learn is stored on your iPhone. If you turn on iCloud sync it goes to your own private iCloud, which we cannot read.
1. Who this covers
This policy covers the Curio iPhone app and this website. It explains what we collect, why, and who else is involved.
2. We do not ask you to identify yourself
Curio has no sign up, no login and no user accounts. We do not ask for your name, email address, phone number, date of birth or location. You can use the entire app without telling us who you are.
3. What is stored on your device
Everything you do in Curio is written to a database on your iPhone:
- Which ideas you have opened and finished
- Your answers, and whether each one was right
- The memory schedule Curio calculates for each idea, meaning its stability, difficulty and next review date
- Your streak, your daily goal and your settings, including whether sound is on
This never leaves your device unless you turn on iCloud sync. Deleting the app deletes all of it.
4. iCloud sync
If iCloud is enabled on your device, Curio can sync your learning history to your own private iCloud database so it follows you to a new phone. Apple stores it under your Apple Account. We have no access to it, no key for it and no way to read it. It is governed by Apple's privacy policy. Turning off iCloud for Curio in iOS Settings stops this.
5. Ask Curio, and generated ideas
Curio has an optional feature that answers a question you type, and can generate an idea on a subject you name. When, and only when, you use it, the text you typed plus the topic it relates to is sent to Google's Gemini API so a reply can be produced.
- Nothing identifying you is attached to that request.
- Your learning history, your answers and your schedule are never sent.
- If you never use the feature, nothing is ever sent.
Google processes it under the Gemini API terms. Do not type anything sensitive or confidential into it.
6. Subscriptions
Curio Plus is bought through Apple's In-App Purchase. We never see your card, your billing address or your Apple Account. Apple tells us only whether a subscription is active.
We use RevenueCat to check that with Apple. RevenueCat receives an anonymous identifier generated on your device and the purchase receipt Apple issues. It receives nothing about what you learn.
7. Notifications
If you allow them, Curio schedules reminders on your device using the review dates it calculated locally. No server is involved and no push service receives your data. You can turn them off in iOS Settings or inside the app at any time.
8. What we do not do
- No advertising, and no advertising identifiers
- No third party analytics or attribution software
- No selling or sharing of personal information, in the sense used by the CCPA and CPRA
- No profiling, and no automated decisions with legal effects
- No tracking across other companies' apps or websites
9. This website
This site is static, sets no cookies and runs no analytics or tracking scripts. Our host, Vercel, keeps short lived server logs that include IP addresses, which is a normal security and delivery measure. See Vercel's privacy policy.
10. Children
Curio is rated for ages 4 and up and contains nothing intended for children specifically. We do not knowingly collect personal information from anyone, children included, because we do not collect personal information at all.
11. Your rights
Rights of access, correction, deletion, portability and objection under the GDPR, the UK GDPR and the CCPA apply to personal data a company holds about you. We hold none, so there is nothing for us to hand over or erase. To erase everything Curio has recorded, delete the app and, if you used sync, remove Curio's data in iOS Settings under your Apple Account and iCloud.
Where processing does occur, the legal basis is performance of a contract, namely running the app you asked for. Data you send to Ask Curio may be processed outside your country by Google under its own safeguards.
12. Changes
If this policy changes in a way that matters, the date at the top changes and the app will say so before the change takes effect.
13. Contact
We answer privacy questions within 30 days.