Privacy Policy

Last updated: November 3, 2026

In short: no sign-up is needed. Your books, bookmarks and settings stay on your device and are never sent anywhere. The app only sends technical crash reports and anonymous usage statistics through Google Firebase.

1. About this policy

This policy explains what data the MP3 Книги mobile app for iOS and Android (“the app”) handles, why, and for how long. “We” means the developer of the app. The policy also covers this website.

By using the app you agree to this policy. If you do not agree with it, please do not use the app.

2. Data that stays on your device

To work, the app keeps the following in your device’s storage:

the audio files and covers of the books you add;
where you stopped in each book, your bookmarks and playback speed;
app settings such as the theme, menu style and sleep timer options.

This data is not sent to us or to anyone else, and we have no access to it. It is deleted when you delete the app. If backups are turned on for your device (iCloud, a computer or Google), it may be included in them according to your system’s rules.

The title and cover of the book that is playing appear on the lock screen, in the playback notification and, on Android, in the home screen widget. This happens on the device and sends nothing anywhere.

3. Crash reports

To find and fix bugs, the app uses Firebase Crashlytics (Google). When the app crashes or hits a serious error, it sends a technical report with:

the device model and the versions of the operating system and the app;
the time of the crash and where in the code it happened (the stack trace), memory and storage state;
a random installation identifier created by Crashlytics, which does not reveal who you are.

4. Usage statistics

To understand how the app is used, it uses Firebase Analytics (Google), which automatically collects anonymous information:

first launch, app updates, and the number and length of sessions;
the device model, system and app versions, and language;
approximate region (country and city), which Google derives from the IP address;
an app instance identifier. On Android, Firebase may also receive the device’s Advertising ID unless you have turned it off in Android settings.

The app has no ads. We do not use this information for advertising and do not link it to your identity.

5. What the app does not collect

The app does not collect or send your name, email address, phone number, contacts, precise location, photos, the titles of your books, file names or the contents of your audio files.

6. Permissions and device features

Photos. The app accesses your photos only when you choose a cover for a book. It receives just the picture you pick and saves it as the cover on your device.
Files. Books are added through the system file picker or the “Open in…” (iOS) and “Open with” (Android) commands. The app receives only the files you choose.
Motion sensor. In the last seconds of the sleep timer, the app watches for a shake of the phone to extend the timer. Sensor readings are not stored or sent.
Local network. While the app is running, it serves a page on your Wi‑Fi network for uploading books (an address like http://192.168.1.24:7777). Devices on the same network can open this page: it shows your books and lets anyone on it add, rename and delete them. Files go directly from the computer to the phone and never pass through the internet or our servers. Keep this in mind on public Wi‑Fi, such as in cafés, hotels and on public transport.
Cover from a link. If you paste an image link on the upload page, the phone downloads the image from that website itself. That website sees your network’s IP address, as with any ordinary page visit.
Background playback. To keep playing with the screen off, the app shows a playback notification (Android) and controls on the lock screen.

7. Who receives data

Crash reports and statistics are processed by Google LLC as the provider of Firebase. The data may be stored on Google servers outside your country, including in the United States. Learn more in the Firebase privacy information and the Google Privacy Policy.

We do not sell data and do not share it with anyone else, except where the law expressly requires it.

The app is downloaded from the App Store and Google Play, and reviews are left there too. These stores handle data under Apple’s and Google’s own policies.

8. How long data is kept

Crash reports are kept in Firebase Crashlytics for 90 days. Usage statistics are kept in Firebase Analytics for no longer than 14 months. Data on your device stays until you delete it or the app.

9. Your choices

Delete a book or bookmark in the app, and it is removed from the device.
Delete the app, and all of its data on the device is removed and no more reports or statistics are sent.
On Android, you can reset or delete your Advertising ID in system settings.
We do not know who you are, so we cannot look up your data by name or email. If you have a question or a request to delete data, write to us and we will do our best to help.

10. This website

This website uses no cookies, visitor counters or third-party scripts, and its fonts are served from this site. The hosting provider may keep standard technical logs (IP address, time and address of the request) to run and protect the site.

11. Children

The app is not specifically directed at children under 13, and we do not knowingly collect their data.

12. Changes to this policy

If this policy changes, we will update it on this page together with the date at the top. We will mention significant changes in the app’s update notes.

13. Contact

Privacy questions and support: help@bookreader.top