Comparison

BiLibre DjVu and PDF Reader vs Learn Kotlin Programming

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

BiLibre DjVu and PDF Reader

Read and organize technical, scientific, and educational literature in DjVu and PDF formats. Features include customizable reading modes, powerful annotation tools, a built-in summary editor, and advanced DjVu processing. Manage your library with smart cataloging and metadata editing.

Highlights
  • Customizable reading modes
  • Annotation and drawing tools
  • Summary editor with Markdown
  • DjVu text recognition
  • Full text searching
  • Library cataloging and metadata editing
  • Cloud synchronization
Features
Read full description

The application for reading and cataloging books, textbooks, reference books and documents in DjVu and PDF formats in a modern, user-friendly style. Designed mainly for working with technical, scientific and educational literature. COMFORTABLE READING MODE • Crops a page margins in manual and automatic mode. • Themes, color schemes for reading (day, night, sepia and more). • Page turn with scroll, curl and slide. POWERFUL ANNOTATIONS • Notes, stickers and scraps. • Drawn annotations (Apple Pencil support and just by touching). • Exports annotations in HTML, PDF, RTF formats. • Synchronization of annotations and drawings in iCloud. • Unified view and management of all annotations in all the books at once. BUILT-IN THE SUMMARY EDITOR • Markdown formatting. • Exports summaries in HTML, PDF, RTF formats. • Synchronization of summaries in iCloud. ADVANCED FEATURES FOR DJVU • Text recognition of pages in DjVu (for documents without OCR layer). • Splits a scanned double-page spread in DjVu into separate pages. WORKING WITH FRAGMENTS OF TEXT • Translation of separate words or complete sentences in different languages. • Full text searching in a book (textual, fuzzy and regular). • Built-in search for a selected text on the Internet, Wikipedia and Wolfram|Alpha. • Search for a word definition in a dictionary. • Text-to-speech in books. • Smart zoom by double-tap. CATALOGUER • Grouping by categories: by authors, subjects, sequences, publishers, tags, popular, recent, new, read and reading now. • Using tags to categorize documents. • Customizable search for books in the library by various metadata fields in different modes. • Search for textbooks on the Internet through arXiv.org, Library Genesis and Google. • Own folders tree and flexible bookshelf settings for layout and sorting. • Arranging books on a bookshelf by dragging. WORKING WITH A METADATA AND A TABLE OF CONTENTS OF A BOOK • Automated extraction of a metadata from PDF and DjVu. • Convenient editing of a metadata. • Editing and creating a table of contents in manual and automatic mode. • Synchronization of a metadata and a table of contents in iCloud. STORAGE • Locally on the device. • In the Cloud Storage (iCloud Drive, Google Drive, Yandex Disk). • Content server for accessing files on the device via a local network. • Import files from shared folders in the local network. • Export files.

About

Learn Kotlin Programming

Features
Read full description

Learn Kotlin Programming is your complete guide to mastering Kotlin, the modern programming language for Mobile app development and other JVM-based applications. Whether you’re a beginner or an experienced developer, this app provides in-depth tutorials, practical examples, and interactive quizzes to help you become a Kotlin expert. Key Features: Comprehensive Tutorials: Learn Kotlin basics, advanced features, and concepts like coroutines, DSLs, and functional programming. Hands-On Examples: Practice with real-world Kotlin examples for mobile apps, server-side applications, and more. Bookmark: Save important lessons for quick access and review anytime. Syntax Highlighting: Follow clean, syntax-highlighted Kotlin code examples for better understanding. Text-to-Speech: Study on the go with tutorials read aloud via the text-to-speech feature. Tips and Tricks: Discover best practices for writing efficient and maintainable Kotlin code. Learn Kotlin Programming is perfect for developers aiming to build Mobile applications, backend services, or improve their programming skills. Download now and start your Kotlin journey today!

Screenshots

BiLibre DjVu and PDF Reader4 screens
Learn Kotlin Programming4 screens

Verdict

The call

The clearest difference is update cadence: BiLibre DjVu and PDF Reader at every 10 days against Learn Kotlin Programming's every 20 months. BiLibre DjVu and PDF Reader also leads on iOS requirement (10.0 vs 13.0). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

BiLibre DjVu and PDF Reader costs $1.99 and Learn Kotlin Programming $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

BiLibre DjVu and PDF Reader ships an update every 10 days, Learn Kotlin Programming every 20 months. The most recent releases landed on October 15, 2026 and October 17, 2026 respectively.

Scorecard2 real differences · 8 level
BiLibre DjVu and PDF Reader versus Learn Kotlin Programming: the parameters behind the verdict, then further details
ParameterBiLibre DjVu and PDF ReaderLearn Kotlin Programming
Price$1.99$1.99
Rating4.3 (103 ratings) — better—
Positive reviews41.1% of reviews—
Number of ratings103 — better—
Update frequencyEvery 10 days — betterEvery 20 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS10.0 — better13.0
Further details — not scored
Size57 MB63 MB
Age rating17+4+
DeveloperKonstantin BukreevMuhammad Mubeen

In-app purchases

None

BiLibre DjVu and PDF Reader

No in-app purchases

None

Learn Kotlin Programming

No in-app purchases

Questions

Is BiLibre DjVu and PDF Reader free?
BiLibre DjVu and PDF Reader costs $1.99, with no in-app purchases.
Is Learn Kotlin Programming free?
Learn Kotlin Programming costs $1.99, with no in-app purchases.
Do BiLibre DjVu and PDF Reader or Learn Kotlin Programming have ads?
Neither BiLibre DjVu and PDF Reader nor Learn Kotlin Programming shows ads.
Which is updated more often, BiLibre DjVu and PDF Reader or Learn Kotlin Programming?
BiLibre DjVu and PDF Reader ships an update every 10 days, and Learn Kotlin Programming every 20 months. Most recently, BiLibre DjVu and PDF Reader was updated on October 15, 2026 and Learn Kotlin Programming on October 17, 2026.

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