Freedom251 › Ebook Reader Software
KyBook 3
What KyBook 3 is
KyBook 3 is an iOS app for reading and cataloging e-books, with macOS also listed as a supported platform. It handles EPUB, PDF, DjVu, MOBI/AZW3, FictionBook, comics, audiobooks, plain text, and rich text. Reading options include day, night, and sepia themes, scrolling, curl or slide page turns, auto scrolling, and text-to-speech. Readers can mark passages, add bookmarks, and draw annotations, then export annotations as Markdown, HTML, PDF, or RTF. KyBook 3 supports OPDS catalogs, includes known catalogs, and lets users add their own, such as a Calibre content server. Storage options include iCloud Drive, Google Drive, OneDrive, Dropbox, Yandex Disk, SMB/CIFS shared folders, and WebDAV. The app can run a content server for Wi-Fi access to device files and stream audiobooks from cloud storage. A subscription is required to synchronize ebook data, files, and reading progress. Pro features require a one-time in-app purchase. The maker lists version 0.7.5 as released February 04, 2019; Apple lists macOS 11 or later on an Apple M1 Mac.
Who it suits
KyBook 3 suits readers who want broad ebook format support, catalog connections, and annotation tools. It may also fit readers who use cloud or network storage, provided their device meets the stated requirements.
What it does well
- Supports ebooks, comics, audiobooks, and text formats
- Exports annotations in four formats
- Connects to OPDS catalogs and listed storage services
- Can stream audiobooks from cloud storage
What to know first
- Synchronization requires a subscription
- Pro mode features require an in-app purchase
- Maker lists version 0.7.5 from February 04, 2019
- Requires a 64-bit device and iOS 11 minimum
Limits
The free download includes in-app purchases. Synchronization requires a subscription, and Pro mode features require a one-time in-app purchase.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Free | Reading and cataloguing; in-app purchases available | Free |
| Yearly subscription | Every year; auto-renewing · Synchronizes ebook metadata and files | $14.99 a year |
| Upgrade to Pro (Discount) | Discounted Pro upgrade | $2.99, paid once |
| 3 months subscription | Every 3 months; auto-renewing · Synchronizes ebook metadata and files | $4.49 a month |
| Upgrade to Pro | Pro features; batch OPDS downloads and batch metadata editing require Pro | $4.99, paid once |
As kybook-reader.com lists them, read 15 Oct 2026. The maker's own page has the final word.
Getting started
- Open the KyBook 3 website or find the app through its iOS or macOS listing.
- Install the free download on a supported device.
- Add books from supported catalogs, cloud services, shared folders or WebDAV.
- Choose a subscription for synchronization or make the one-time Pro purchase for Pro mode features.
Verdict
KyBook 3 offers a wide range of reading formats, annotation exports, and catalog and storage connections. Sync and Pro features have separate purchase requirements, and the maker lists an older release date.
Questions
Is KyBook 3 free?
The Free plan costs nothing and is a free download with in-app purchases available.
How much do the paid plans cost?
The 3 months subscription is $4.49 a month, billed every 3 months. The Yearly subscription is $14.99 a year, billed yearly. Upgrade to Pro is $4.99, paid once as a one-time in-app purchase.
Which platforms does it support?
iOS and macOS are listed. The maker says it requires a 64-bit device and iOS 11 minimum; the App Store lists macOS 11 or later on an Apple M1 Mac.
What file formats can it read?
Formats include DRM-free EPUB and PDF, MOBI, AZW3, DjVu, FB2, FB2.ZIP, CBR, CBZ, CBT, MP3, M4A, M4B, TXT and RTF.
What does the subscription include?
A subscription is required for synchronization of ebook metadata, files, reading positions, bookmarks, annotations, reviews and summaries.
Who makes KyBook 3?
The App Store identifies Konstantin Bukreev as the app's developer and seller.
Facts from KyBook 3's own pages
- Annotations
- Readers can highlight, bookmark and draw annotations with Apple Pencil or touch, then export them as Markdown, HTML, PDF or RTF. · apps.apple.com, 15 Oct 2026
- API and SDK
- The reviewed official pages describe no public KyBook API, SDK or developer integration interface. · kybook-reader.com, 15 Oct 2026
- Catalogs
- It supports OPDS catalogs, includes a list of known catalogs and allows users to add their own, such as a Calibre content server. · github.com, 7 Oct 2026
- Company identity
- The App Store identifies the seller and developer as Konstantin Bukreev. · apps.apple.com, 15 Oct 2026
- Content server
- A built-in content server exposes device files over Wi-Fi through a web browser. · apps.apple.com, 15 Oct 2026
- Device requirements
- The maker's page says KyBook 3 requires a 64-bit device and iOS 11 minimum; the App Store lists iPhone and iPad compatibility and macOS 11 or later on an Apple M1 Mac. · github.com, 7 Oct 2026
- Documentation
- The official help URL exists, while the public site repository provides feature pages and a dated changelog rather than an API manual. · kybook-reader.com, 15 Oct 2026
- Formats
- It supports EPUB, PDF, DjVu, MOBI/AZW3, FictionBook, comic book, audiobook, plain text and rich text formats. · github.com, 7 Oct 2026
- Latest listed version
- The App Store lists version 0.7.8, released February 23, 2019. · apps.apple.com, 15 Oct 2026
- Library organization
- Cataloguing supports categories, tags, collections, folder trees, flexible sorting and drag-and-drop shelf arrangement. · apps.apple.com, 15 Oct 2026
- Licence
- The public KyBook GitHub repository lists README, screenshots and issues but no license file is shown in its repository file list. · github.com, 15 Oct 2026
- Limit: interface and performance
- Independent reviewers mention a reading interface needing improvement, lag, awkward highlighting and subscription-gated features. · assets-global.website-files.com, 15 Oct 2026
- Limit: open issues
- The public issue tracker shows 461 open issues, including sync, registration, freezing, highlighting, text-to-speech and Calibre-server problems. · github.com, 15 Oct 2026
- Limit: support responsiveness
- App Store reviews describe unanswered bug reports and certificate-related sync failures. · apps.apple.com, 15 Oct 2026
- Limit: synchronization
- Reviewers report that cross-device synchronization and account creation often fail, including after paying for the subscription. · justuseapp.com, 15 Oct 2026
- Limit: update stagnation
- Reviewers complain that the app has gone years without releases and fear it has been abandoned. · apps.apple.com, 15 Oct 2026
- Maker and seller
- The App Store identifies Konstantin Bukreev as the app's developer and seller. · apps.apple.com, 7 Oct 2026
- Metadata and contents
- KyBook extracts metadata automatically and lets users edit metadata and create or edit tables of contents. · apps.apple.com, 15 Oct 2026
- Notable changelog
- The February 4, 2019 release fixed Chinese OCR language-pack downloading and reading-time calculation issues. · github.com, 15 Oct 2026
- OPDS
- Users can browse built-in OPDS catalogs, add their own catalogs such as Calibre servers, and reach onion OPDS catalogs through Tor. · apps.apple.com, 15 Oct 2026
- OPDS over Tor
- The maker's page says the app supports .onion OPDS catalogs reachable via the Tor Network. · github.com, 7 Oct 2026
- Other capabilities
- The app can run a content server for accessing device files over Wi-Fi and supports streaming audiobooks from cloud storage. · github.com, 7 Oct 2026
- PDF and DjVu tools
- PDF and DjVu support includes manual or automatic margin cropping, double-tap zoom, PDF reflow on iPhone and OCR. · apps.apple.com, 15 Oct 2026
- Praise: customization
- JustUseApp reviewers repeatedly praise the large amount of customization and broad format support. · justuseapp.com, 15 Oct 2026
Where KyBook 3 stands on Freedom251
- Ebook Reader Software#16 of 27