Privacy Policy

This policy explains how Paperi, operated by Ing. Petr Bobák, Ph.D., Kleštínek 381/14, 621 00 Brno, Česká republika (the “controller”), processes personal data under the EU General Data Protection Regulation (GDPR).

1. What we collect

• Documents you upload — the PDFs you submit, and the text and figures extracted from them, in order to make your walkthrough.
• Email address — when you ask to be emailed when your video is ready, join the waitlist, subscribe, or request an access link.
• Technical data — IP address and request metadata, used for security, abuse prevention, and rate limiting.
• Subscription data — for paying users, billing details are handled by Stripe; we store your customer/subscription identifiers, status, and the email used at checkout (not your card number).
• A functional cookie (vp_uid) — a signed identifier that ties your library and subscription to your browser. It is strictly necessary for the Service and is not used for advertising.
• Anonymous visit statistics — we count page views, how long a page was open in a visible tab and how far down it was read, which of our buttons and outgoing links were used, and whether a walkthrough was played and roughly how far it ran, to see which pages are used, which walkthroughs are watched, and where visitors arrive from. A small script of our own on each page reports this to our server; nothing is sent anywhere else. This uses no cookie and no tracking pixel: your IP address and browser string are combined with a random value that changes every day and are turned into a one-way code, and the originals are discarded — they are never stored. Before that, the IP address is used to look up the country only, and the browser string to tell a phone, tablet or computer apart; only those words are kept. Because the daily value is deleted, the code cannot be traced back to you and cannot link your visits from one day to the next. The statistics are first-party, aggregate, for our own use only, and are never shared, sold, or used to build a profile or to advertise.

2. Why, and our legal basis

• To provide the Service (process your document, deliver the video, keep your library) — performance of a contract.
• To send transactional email (your link, billing notices) — contract.
• To secure the Service and prevent abuse (IP, rate limits) — legitimate interests.
• To understand how the site is used, via the anonymous visit statistics above — legitimate interests.
• To meet tax and accounting obligations for payments — legal obligation.

3. Processors and third parties

We share data only with providers that process it on our behalf:

• AI model provider (openrouter) — the text and figures of your uploaded document are sent to a third-party AI provider to generate the script and narration. Do not upload confidential material you are not comfortable processing this way.
• OpenAlex — to credit the paper you upload with its authors and a link to it, we look up its DOI or title in this open, non-profit index of published research. Only that identifier or title is sent: never the file, and never who uploaded it.
• Stripe — payment processing for subscriptions.
• Email delivery (Resend) — to send your notifications and access links.
• Hosting / infrastructure — to run the Service.

Some providers may process data outside the EEA; where they do, transfers rely on appropriate safeguards such as the EU Standard Contractual Clauses.

4. Retention

On the free tier, the PDF you upload is deleted after about 7 days. The walkthrough made from it, including the images of the paper's pages it shows, is available at its link for 30 days and is then archived: it is no longer shown to anyone, and it is restored if you subscribe to Reader. Walkthroughs made with Reader stay available while you subscribe and for 30 days after it ends, and are then archived in the same way. Archived walkthroughs are deleted 12 months after they were archived. You can delete any walkthrough yourself at any time, from its page, and you can request erasure at any time. Paid Studio videos stay available until you delete them or close your account; unfinished Studio drafts are shown only to you and the reviewers you share them with, until you delete them. Account, subscription, and billing records are kept as long as needed for the Service and to meet legal obligations. Security logs are kept for a limited period. Anonymous visit statistics are kept for 90 days.

5. Your rights

Under the GDPR you may request access, rectification, erasure, restriction, portability, and object to processing based on legitimate interests. To exercise these rights, contact hello@paperi.ai. You also have the right to lodge a complaint with the Office for Personal Data Protection (ÚOOÚ), Czech Republic.

6. Children

The Service is not directed at children and is intended for users who can enter into a contract.

7. Changes & contact

We may update this policy; material changes will be posted here. Data protection contact: hello@paperi.ai.