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56
BU Score
Solid

zLibrary - EPUB Reader & PDF

4.2 ✍️ Editor
✍️ BU Analytics Review

zLibrary - EPUB Reader & PDF is an iOS app from AppStance LLC in the Food & Drink category, currently rated 4.2★ across 597 ratings. Initial signal reads as mixed reviews — supporters praise core features while critics cite stability/value gaps.

Our BU Score puts it at 56Solid (established niche player). For a Food & Drink app, that means established niche player.

Track changes month-over-month in the Performance section below — live snapshot history and revenue forecast included.

creator

📊 Performance Tracking LIVE

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idle
0%
Rating
Reviews
Forecast Revenue / mo
Snapshots tracked
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since first record
Range:

💰 Forecast Revenue / mo

MODEL
Revenue forecast computed from BU's 234 trigger model on each snapshot. Calibrated against ground-truth from 58 verified-revenue apps.
🔬Forecast Breakdown — Why This Estimate?Top 6 of 6 triggers
Our ML model uses 200+ signals from public data. These are the most influential for this app:
cancelledREVIEW
−$1,500
Good rating (4.2★)METRIC
+$800
Established app (4y old)METRIC
+$800
Ad-supported / freemiumMETRIC
+$600
Early-stage install base (597 ratings)METRIC
+$400
Single-language (English only)METRIC
−$400
METRIC = structural app data · REVIEW = mined from user reviews · ✓ VERIFIED = Stripe-verified anchor (TrustMRR)

📈 Reviews Growth

LIVE
Cumulative review count from first BU snapshot. Each point = a tracked update.
💚Sentiment Over Time↑ green = positive · ↓ red = negative
Jun 24
Jul 24
Aug 24
Sep 24
Nov 24
Jan 25
Apr 25
May 25
Aug 25
Sep 25
Jan 26

⭐ Rating Trend

LIVE
Average rating evolution. Updates with each new review batch.

🗓️ Snapshot Timeline

HISTORY
Each bar shows a tracked update and the metric delta from the previous snapshot.
App Specs
🔐 Own this app? Claim & verify MRR →
💾 57 MB🔞 12+📱 iOS 13.0+🔖 v2.4🔄 updated 3y ago🌐 EN📂 Food & Drink💰 Free🚀 Launched 2021 (4y old)

📝 About this app

Explore our library with more than 60000 curated ebooks from the public domain. The minimalist design makes it easy to browse by popular books, authors, or content tags from any selection. Offline reading means that once you open a book, it is downloaded to your library and available for reading at any time.

The app home screen lists popular, classic works and is an excellent place to start browsing. Every book you open is stored in your library, and you can adjust the reading settings to change the font size of the books and switch between dark mode and classic white mode. The reader also allows you to choose ambient sounds and music to enjoy as your read. Choose from a selection that includes ocean sounds, rain, and morning birds to set the mood as you read.

You can also use our ebook reader to upload books from your icloud/files or from a link. Enjoy all the features of our ebook reader with a book of your choice that might not be available in our public domain library.

App features:
* Every book you start reading will automatically be saved in your Library. Every book in your library is downloaded and available for offline reading.
*Import books from other apps to read within the ebook reader.
*Listen while you read — play a selection of ambient sounds and music to enjoy in the background of your reading.
* The 'Authors' menu shows the most popular authors whose books you can find on the app. Click on the author’s name to view a list of all of that author’s works available. Author selections include Mark Twain, Frederick Douglass, Edith Wharton, Washington Irving, Harriet Jacobs, Mary Shelley, Kahlil Gibran, Jane Austen, Homer, Charles Dickens, Arthur Conan Doyle, Lewis Carroll, and many others.
* The intuitive, minimalist functions make it easy to jump between titles, authors, and tags to explore the ocean of books available until you find something you’d like to save to your library.
* Once you tap on a book, you will see the 'Book Info' page. This displays the title, author, language, content tags, and a description of the book. Simply tap 'Read' button to open the book in the eBook reader.
* Once you open the book, it will be automatically downloaded to your device and saved in your Library.
* From the eBook reader, access the table of contents to jump to specific chapters. You can turn pages using by swiping or scrolling.
* Delete books from your library at any time.

We welcome and appreciate your feedback.

And now with Premium subscription you can:

+ Access more than 60000 curated books instantly
+ Import unlimited ebooks
+ Unlock all sounds and music
+ Powerful Search functionality of our collection
+ Share the subscription with your family
+ 7 day free trial with yearly subscription

Attribution 4.0 International (CC BY 4.0)
https://creativecommons.org/licenses/by/4.0/

https://www.freesoundslibrary.com
https://dilipreddy.com/new-dawn
https://musopen.org

Spring Flowers by Keys of Moon | https://soundcloud.com/keysofmoon
Music promoted by https://www.chosic.com/free-music/all/

This public domain content was made possible by Project Gutenberg and Standard ebooks organizations.

To have access to the Premium content and functionality, you can choose between a monthly or yearly auto-renewable subscription. This is a recurring transaction that will be charged to your iTunes Account at confirmation of purchase and will automatically renew unless you cancel it at least 24 hours before the end of your subscription. Renewals will be charged the same cost within 24 hours prior to the end of the current period. You can manage your subscriptions and auto-renewal can be turned off by going to your iTunes Account Settings after purchase.

Privacy Policy: https://bookdark.com/privacy-policy
Terms of use: https://bookdark.com/terms-and-conditions

🆕 What's New · v2.4

- Added more than 60000 ebooks to read in more than 20 languages.
- We redesigned the ebook reader that tracks your progress.
- Instantly read and download thousands of curated quality public domain books from our collection.
- Listen to ambient sounds or music while you read.
- Customize your reader with Theme, Dark mode, font size, page margin, and font type.
- You can import your epub or pdf ebooks into your library.
- Performance improvements.

We appreciate your support, please leave us feedback.

Profile & Insights

Everything we know — and don't — about this app and its company.

Identification

App name
zLibrary - EPUB Reader & PDF
Developer
AppStance LLC
Bundle ID
com.resdev.bookdark
App Store URL
Open in App Store
Category
Food & Drink
Content rating
12+
Languages
EN

Company

Website
freemusicandbooks.com
Tagline
We make free iOS apps for books, audiobooks, inspirational quotes and affirmations with background music.
Description
We make free iOS apps for books, audiobooks, inspirational quotes and affirmations with background music.
Founded
Not found
HQ / Address
Not found
Employees
Not found
Logo
OG image

Revenue

Verified revenue / mo
Not found
AI revenue estimate / mo
Not found
AI annual estimate
Not found
ML model estimate / mo
$430/mo
Top-grossing rank
Outside top 100 in US Food & Drink
All-time revenue
Not found
Pricing
Not found

Founder

Name
Not found
X / Twitter
Not found
LinkedIn
Not found
GitHub
Not found
X followers
Not found
Public statements
Not found

Funding

Total raised
Not found
Last round
Not found
Investors
Not found
Crunchbase
Not found
AngelList
Not found

Press & Links

Articles found
Not found
Listed on
Not found
Blog
Not found
Press / News
Not found

Contacts & Socials

Socials
Not found
Email
Not found
Phone
Not found
Contact page
Not found
About page
Not found
📈Ratings growth597 ratings+59600% lifetimeShow 3-year history estimate ▾Sep 2021May 2024May 2026
Tracked (44 weeks) Pre-tracking estimate (36 weeks) · model-based, ±5% noise · anchored to release date and current value
🌍Geographic ReachNot ranked
This app is currently outside the top 100 grossing in all 9 countries we monitor (US, UK, DE, FR, JP, CA, AU, BR, IN). Niche or new apps often launch this way — popularity rankings appear once daily revenue clears the regional threshold.
Profile is built from iTunes Lookup + developer site scrape + ML revenue model. Empty fields show "Not found" — additional sources (Crunchbase, X, IndieHackers, Acquire.com) coming.
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