Privacy Policy

Version 2 · effective September 10, 2026 · controller: Allan Serrano (contact@librumapp.com), Costa Rica · Terms of Use · Español

This is an English translation provided for convenience. The Spanish version at librumapp.com/privacidad is the governing text; if the two ever differ, the Spanish version prevails.

Librum is an app for readers. This document says, plainly, what data we keep, what for, what is visible publicly and what we never do. It is written to be read in full: if something here is unclear, write to us and we will rewrite it.

What we keep

• Your account: your email and your password (encrypted; we cannot see it).
• Your reading: progress, pages per day, streak, library and sections, ratings, reviews, notes, goals, challenges, achievements and the guides you activated.
• Your profile: name, country, bio and your preferences about what to show.
• The photos you upload, if any: your profile photo and a club's cover. You choose them with the phone's picker; Librum does not look at the rest of your photos.
• Your purchases: which plan you have and the history of your Codex purchases, as reported to us by the store (Apple or Google) or the web reseller. We never see your card or payment details.
• What you write to us: the feedback you send from the app and, if you write to an author, your question.
• Your devices, only if you turn on notifications: the browser's notification subscription (not your phone number or your location).
• How you use the app: which screens you open, whether you installed it, whether you accepted or declined notifications, whether you finished the tutorial and what you searched for without finding it. It helps us see where the app gets in the way. It is kept for 180 days and deleted with your account. We use no third-party trackers: this data lives in the same database as everything else and never leaves Librum.
• That you accepted this policy: the version you saw and when.

What we use it for

To give you the app: syncing your reading across your devices, calculating your streak and your statistics, building your guides and recommendations, sending you the notifications you asked for, and replying when you write. Nothing else.

What is private and what is visible

Your profile is private by default. Your notes are always private. Whatever is visible is visible because you turned it on:

• Your public profile and your appearance on the leaderboard are two separate switches, both off until you turn them on.
• A review is shared only if you mark it as shared.
• Asking an author a question makes your name public next to the question, on that author's profile, if the author decides to answer it. The question does not appear before it is answered.
• RSVPing to an event shows your name to the author only if you tick the box that says so. Without it, the author sees the number of attendees, not who they are.
• Being someone's friend lets them see your profile and your reading activity, even if your profile is private to everyone else.
• A book club shows its members the shared progress on the club's book.

Who it is shared with

Aggregated, anonymous statistics for bookstores, publishers and authors

Librum will share aggregated figures with bookstores, publishers and authors about the books in their own catalog. This is exactly what they can see, and nothing more:

• How many people want to read a book (have it on "want to read").
• How many are reading it now, and at what average pace.
• How many finished it, and how many abandoned it (and, on average, where).
• The average star rating and how many reviews it has.
• Breakdown by country and by month, when the numbers allow it (see the threshold).

With four safeguards:

• Threshold of 25. A figure is shown only if it comes from at least 25 people. Below that nothing is shown, not even "fewer than 25", because with few cases an aggregate stops being anonymous. The threshold also applies to each breakdown (by country, by month).
• Never who. Your name, email, profile or any list of readers never travels, and there is no way to ask us "give me this book's readers" or to cross two figures to deduce it. Aggregates are calculated in our database and only the total leaves.
• You can opt out. In "My account → Privacy and my data" there is a switch so your reading is not counted in any aggregate. It changes nothing else in the app.
• No data sales. These aggregates may be part of a paid service for bookstores and publishers; what is paid for is the report, never your data. And Librum does not sell or share identifiable data for any amount.

Authors on Librum

An author (or the imprint that manages them) can claim their profile and, once their identity is verified, publish on it: their bio, links, points of sale, news, events and answers to the questions they receive. What they see about you is what is listed above: your name on a question they answered, your name on an event if you allowed it, and aggregated figures with the threshold of 25. They cannot message you privately (there are no direct messages between author and reader) and they are not notified when you write a review of their book.

Author notifications

If you follow an author, Librum sends you notifications about what they publish. You can turn them off per author or entirely, whenever you want, and following someone does not reveal your email to them.

Service providers

Librum runs on third-party services that process data on our behalf and do not use it for their own purposes: Supabase (database and accounts), Amazon Web Services (where the app is served), Resend (account emails), RevenueCat (keeps the record of purchases made inside the app, together with Apple and Google, which charge you), Anthropic (the AI features: the copilot, the summaries and the guides) and the public book catalogs (Google Books, Open Library, ISBNdb) to fetch covers and book data. The AI receives the book, your reading position and what you ask it (for recommendations, also your finished books, your ratings and your favorite genres and authors), never your name, your email or your account details.

Covers and images

Book covers and book data come from public catalogs, and an author can upload the cover of their own work. So that they load quickly and do not break over time, Librum hosts a copy of those images on its own server. The rights still belong to whoever holds them.

Image takedown. If you are the rights holder (author, publisher, illustrator) and want a cover to stop being shown, write to contact@librumapp.com with the title, the ISBN if you have it and the link to the book. We remove it and the book is left without an image; we reply within 10 business days. The same applies to an author photo.

Your control

• View and correct: your profile and your reading can be edited in the app.
• Export: your library as CSV and your notes as Markdown, from the app.
• Delete everything: "My account → Delete my account and data" erases your account and your data forever. There is no courtesy copy or grace period: once you confirm, it is gone.
• Turn off notifications: reminders, quotes and author notifications can be turned off separately, without deleting anything.
• Change your email: from "My account → Change email"; we ask you to confirm in both the new and the current address.
• Opt out of aggregates: the switch in "My account → Privacy and my data" (see above).
• Ask: any question about your data, contact@librumapp.com.

What Librum does not do

• It does not sell or transfer identifiable data, to anyone, for any amount.
• It shows no third-party advertising and uses no advertising trackers.
• It does not read or publish your notes: they are private, always.
• It does not notify an author that you wrote a review of their book.
• It does not open private messages between an author and you.
• It does not process payments for books: when you buy one, it sends you to the author's or bookstore's point of sale and the transaction happens there, outside Librum.
• It does not use your data to train AI models.
• It uses no third-party trackers or analytics: what it measures, it measures in its own database.

How long we keep it

Your reading, your library and your notes: as long as you have an account. App usage data: 180 days. The log of each notification sent: 30 days. Database backups, which exist so your reading is not lost if something fails: 90 days, encrypted, in private storage; deleted data disappears from a backup when that backup expires.

Children

Librum is not directed at children under 13. If we learn that an account belongs to a child under 13, we delete it.

Changes

When this policy changes substantively, its version number goes up and we let you know inside the app before you keep using it; tapping "Got it" records which version you saw. The version and date are at the top of this document.

History

• Clarifications (October 20, 2026), no version change: photos and purchases are named among the data we keep, RevenueCat among the providers, and what is sent to the AI for recommendations. Nothing about what is done with your data changes. This English translation is published.
• Version 2 (September 10, 2026): details which aggregated figures bookstores, publishers and authors can see, and with which safeguards; adds the opt-out switch; explains app usage data, recorded acceptance, email change and retention periods. The terms of use are published.
• Version 1 (August 23, 2026): first public version.