KyBook 3 Ebook Reader vs Readest
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
KyBook 3 Ebook Reader
This app is a versatile e-book reader and cataloger supporting numerous formats like EPUB, MOBI, and PDF. It offers a comfortable reading experience with customizable options, powerful annotation tools, and seamless cloud storage integration. Organize your library with tags, collections, and a handy cataloguer.
- Supports all major e-book formats
- OPDS catalog access
- Comfortable reading mode with themes
- Powerful annotations and summary editor
- Handy cataloguer with tagging
- Cloud storage integration
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KyBook is the application for reading and cataloging e-books in a modern, user-friendly style. KyBook supports all the major e-book formats, OPDS catalogs and Cloud Storage. Key features • All the major e-book formats • OPDS catalogs • Comfortable reading mode • Powerful annotations • Handy cataloguer • Cloud Storage Ebook Formats • EPub (DRM-free) • PDF (DRM-free) • MobiPocket and Kindle (mobi, azw3) • DjVu • FictionBook (fb2, fb2.zip) • Comic Book (cbr, cbz, cbt) • Audio Book (mp3, m4a, m4b) • Plain and rich text (txt, rtf) OPDS Catalogs • Provides access to enormous collection of free electronic books through OPDS-catalogs support. • Built-in list of well-known OPDS Catalogs • Allows add own catalog (e.g. Calibre content server) • Supports for .onion OPDS Catalogs reachable via Tor Network Comfortable reading mode • Themes, color schemes for reading (day, night, sepia and more). • Page turn with scroll, curl and slide. • Designed to be fast, energy efficient, optimized for very large books (books in millions of words) • Auto scrolling mode • Text-to-speech technology to voice any e-book EPUB/FB2/MOBI specific features • Customizable font, text size, page margins, paragraph indentation, background and more • Typography aware (hanging punctuation, hyphenations and more) PDF/DJVU specific features • Crops a page margins in manual and automatic mode • Smart zooming by double-tap • PDF Reflow on iPhone • Page text recognition (OCR) Powerful annotations • Marked text and bookmarks • Drawn annotations in any ebook (Apple Pencil support and just by touching). • Annotations exports in Markdown, HTML, PDF, RTF formats. Built-in the summary editor • Markdown formatting. • Exports summaries in Markdown, HTML, PDF, RTF formats. Working with fragments of text • Translation of separate words or complete sentences in different languages. • Search for a word definition in dictionaries. • Custom dictionaries in Dictd, StarDict and Lingvo DSL format • Full text searching in a book (textual, fuzzy and search using regular expressions). • Built-in search for a selected text on the Internet or Wikipedia. Handy cataloguer • Grouping by categories: by authors, subjects, sequences, publishers, tags, popular, recent, new, unread, reading and finished. • Tags and collections to categorize ebooks. • Search for books in the library and anywhere in the Internet. • 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 • Automated extraction of a metadata from ebooks. • Convenient editing of a metadata. • Editing and creation (automatic or manual) of a table of contents. File Storage • Locally on the device. • In the Cloud Storage (iCloud Drive, Google Drive, OneDrive, Dropbox, Yandex Disk). • In the Local network on Shared Folders (SMB/CIFS) or on WebDAV server • Transparent caching of books in the Internet or Local network. • Supports of streaming audio books in Cloud Storage. • Content Server for accessing files on the device via a WiFi. Synchronization (requires subscription) • Syncs all ebooks metadata and files. KyBook offers the following subscriptions options: • 3 months: 4.49 USD • 1 year: 14.99 USD Prices may vary in other countries respecting your local currency exchange rate. Your subscription will be charged to your iTunes account. At the end of the term, unless auto-renewables subscriptions are disabled, your subscription will automatically renew in your iTunes account. You will be charged for the regular price of your subscription within 24 hours prior to the end of the current term. You can turn off automatic renewal in your iTunes account settings at any time, but you must do so at least 24 hours before the end of the current term. Refunds will not be provided for the unused portion of any term. Terms & Privacy policy http://kybook-reader.com/terms http://kybook-reader.com/privacy-policy
Readest
This app is a powerful ebook reader designed for deep thinkers and researchers. It offers advanced annotation tools, seamless device syncing, and robust library management with OPDS and Calibre support. Enjoy a distraction-free reading experience with customizable modes and multi-book viewing for enhanced study and analysis.
- OPDS Online Libraries
- Calibre Integration
- Sync Across Devices
- Bookshelf Management
- Customizable Reading Modes
- Multi-Book View
- Advanced Annotations & Highlights
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Readest is an ebook reader for people who read a lot, and who want their books, notes and reading position on whatever device is nearest. Open EPUB, PDF, MOBI, AZW3, FB2, CBZ, TXT and Markdown in one library. Pull books from OPDS catalogs or from your own Calibre server. Read, annotate, listen, translate. Made for iPhone and iPad • CarPlay, so you can keep listening on the road with playback controls on the dashboard • Download read-aloud voices per book and listen with no connection at all • Add books from Files, Mail or any share sheet, and read them in place instead of copying them into a second library • Open up to four books at once on iPad and arrange them how you like Reading • Paginated or scrolling, with custom fonts, themes, spacing and margins • Vertical text for CJK books • Contrast and refresh tuned for e-ink screens • Full-text search inside a book Your library • Browse, search and download from OPDS catalogs and public libraries • Connect to Calibre or Calibre-Web, covers and metadata included • Organize with bookshelf groups you can rename Notes • Highlights, bookmarks and structured notes • Copy a highlight together with a deep link back to the passage • Export your annotations Listening and languages • Text-to-speech with downloadable offline voices • Translate a sentence, a page, or an entire book • Wikipedia and dictionary lookup without leaving the page Sync • Readest Cloud, or bring your own: iCloud, Google Drive, OneDrive, WebDAV, S3 • KOReader sync keeps your progress in step with your e-reader • iPhone, iPad, Mac, all other platforms and the web Readest is open source. Support: support@readest.com Privacy Policy: https://readest.com/privacy-policy Terms of Service: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Screenshots
Verdict
KyBook 3 Ebook Reader and Readest both sit at 4.7 stars, but that hides the real split: 84% of Readest's written reviews are positive against 61% of KyBook 3 Ebook Reader's. Readest also leads on chart position (#209 vs unranked). KyBook 3 Ebook Reader's advantage is ratings volume (4.7K vs 195) and update cadence (every 5 days vs fortnightly). On price, rating, ads and in-app purchases 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
Both are free to download. KyBook 3 Ebook Reader sells 4 in-app purchases, starting at $4.49 per 3 months and Readest sells 9 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.
On the App Store both sit at effectively the same score — 4.7 for KyBook 3 Ebook Reader against 4.5 for Readest. That said, the two scores are not equally well evidenced: KyBook 3 Ebook Reader has 4.7K ratings behind it against 195, so its average is the more settled of the two. Written reviews are what separate them: 61% of KyBook 3 Ebook Reader's written reviews are positive against 84% of Readest's.
KyBook 3 Ebook Reader ships an update every 5 days, Readest fortnightly. The most recent releases landed on October 23, 2026 and October 22, 2026 respectively.
| Parameter | KyBook 3 Ebook Reader | Readest |
|---|---|---|
| Price | Free | Free |
| Rating | 4.7 (4.7K ratings) — better | 4.5 (195 ratings) |
| Positive reviews | 60.9% of reviews | 84.2% of reviews — better |
| Number of ratings | 4.7K — better | 195 |
| Update frequency | Every 5 days — better | Fortnightly |
| Ads | No | No |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Best chart rank | — | #209 — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Mac |
| Requires iOS | 11.0 — better | 16.4 |
| Further details — not scored | ||
| Size | 53 MB | 58 MB |
| Age rating | 17+ | 4+ |
| Developer | Konstantin Bukreev | Bilingify LLC |
Customer experience
KyBook 3 Ebook Reader
Readest
Bugs and requests
KyBook 3 Ebook Reader
Reported bugs
5 issues- Inability to open/read certain file formats
- Sync and account creation issues
- Problems with PDF and image display
- Crashes and compatibility problems
- Duplication of books in library
Requested features
6 requests- Left alignment option
- Dark mode/OLED black theme
- Improved image handling
- Better support for Chinese language
- Vertical page flip
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- Improved text-to-speech capabilities
Readest
Not enough reviews yet to summarise bugs or requests.
In-app purchases
KyBook 3 Ebook Reader
- 3 months subscription7 Days trial$4.493 Months
- Yearly subscription7 Days trial$14.991 Year
- Upgrade to Pro (Discount)$2.99
- Upgrade to Pro$4.99
Readest
- Subscribe to Plus Plan$4.991 Month
- Subscribe to Pro Plan$9.991 Month
- Subscribe to Plus Plan$49.991 Year
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- Subscribe to Pro Plan$99.991 Year
- 1 GB$9.99
- 2 GB$14.99
- Full Customization$19.99
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- 5 GB$29.99
- 10 GB$49.99
Questions
Is KyBook 3 Ebook Reader free?
Is Readest free?
Which has better reviews, KyBook 3 Ebook Reader or Readest?
Do KyBook 3 Ebook Reader or Readest have ads?
Which is updated more often, KyBook 3 Ebook Reader or Readest?
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