Terms of Service

Last updated: October 18, 2026

1. The service

Unknown is an app for Mac, iPhone and iPad, with a web reader at unknown.ac/listen, that converts documents you own (PDFs, EPUBs, Word files, images and web links) into interactive, narrated audiobooks. On a Mac, documents are converted and narrated locally on your device. On iPhone, iPad and the web, documents are converted by our cloud processing service, described in the Privacy Policy. By downloading or using the app you agree to these terms. If you got Unknown from the App Store, Apple's Standard End User License Agreement also applies.

2. Your content

You keep all rights to the documents you open with Unknown. You are responsible for ensuring you have the right to use the documents you convert. When you use cloud processing, the document or link you add is sent to our processing service only to convert it, and the result is deleted after the retention period in the Privacy Policy. We never read your documents or use them to train AI models.

3. Subscriptions

The free plan includes a limited number of narrated pages per month on the Mac, and 2 free documents on iPhone and iPad.
Unknown Pro is an auto-renewing subscription (weekly $2.99, monthly $4.99, or yearly $49.99 in USD; local prices may vary) that removes those limits.
Subscriptions renew automatically until cancelled. You can cancel anytime from the subscription management page linked in your purchase receipt; access continues until the end of the paid period.
Subscriptions bought in the iPhone or iPad app are billed by Apple to your Apple ID when you confirm the purchase, or when a free trial ends. They renew automatically unless cancelled at least 24 hours before the end of the current period, and you manage or cancel them in your App Store account settings.
Subscriptions bought on the Mac or the web are processed securely by Stripe, with RevenueCat keeping your subscription status in sync. We do not see or store your card details.

4. Privacy

On a Mac, your books and audio stay on your Mac. Documents you add on iPhone, iPad or the web are converted on our servers and then deleted, and your reading progress, notes and bookmarks sync between your devices through your account. The app collects basic diagnostic and usage signals (crashes, feature usage) to keep the app working well, never the contents of your documents. Purchases require an account so your subscription can be restored across devices. See the full Privacy Policy.

5. Acceptable use

Don't use Unknown to infringe copyright, redistribute generated audio of works you don't have rights to, or attempt to reverse engineer, resell, or misuse the app or its services.

6. Disclaimer

Unknown is provided "as is" without warranties of any kind. To the maximum extent permitted by law, we are not liable for any indirect or consequential damages arising from use of the app.

7. Changes

We may update these terms from time to time; the latest version will always be at this page. Continued use of the app after changes means you accept the updated terms.

8. Contact

Questions? Reach us at support@unknown.ac.

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