KyBook 3

What it is

Spec sheet

What it does

KyBook 3 is an iOS ebook reader and library cataloguer supporting major formats, OPDS catalogs and cloud storage.Read 15 Oct 2026 · github.com

Purpose

KyBook 3 is an iOS application for reading and cataloging e-books.Read 7 Oct 2026 · github.com

Annotations

Readers can highlight, bookmark and draw annotations with Apple Pencil or touch, then export them as Markdown, HTML, PDF or RTF.Read 15 Oct 2026 · apps.apple.com

API and SDK

The reviewed official pages describe no public KyBook API, SDK or developer integration interface.Read 15 Oct 2026 · kybook-reader.com

Catalogs

It supports OPDS catalogs, includes a list of known catalogs and allows users to add their own, such as a Calibre content server.Read 7 Oct 2026 · github.com

Company identity

The App Store identifies the seller and developer as Konstantin Bukreev.Read 15 Oct 2026 · apps.apple.com

Content server

A built-in content server exposes device files over Wi-Fi through a web browser.Read 15 Oct 2026 · apps.apple.com

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.Read 7 Oct 2026 · github.com

Documentation

The official help URL exists, while the public site repository provides feature pages and a dated changelog rather than an API manual.Read 15 Oct 2026 · kybook-reader.com

Formats

It supports EPUB, PDF, DjVu, MOBI/AZW3, FictionBook, comic book, audiobook, plain text and rich text formats.Read 7 Oct 2026 · github.com

Latest listed version

The App Store lists version 0.7.8, released February 23, 2019.Read 15 Oct 2026 · apps.apple.com

Library organization

Cataloguing supports categories, tags, collections, folder trees, flexible sorting and drag-and-drop shelf arrangement.Read 15 Oct 2026 · apps.apple.com

Licence

The public KyBook GitHub repository lists README, screenshots and issues but no license file is shown in its repository file list.Read 15 Oct 2026 · github.com

Limit: interface and performance

Independent reviewers mention a reading interface needing improvement, lag, awkward highlighting and subscription-gated features.Read 15 Oct 2026 · assets-global.website-files.com

Limit: open issues

The public issue tracker shows 461 open issues, including sync, registration, freezing, highlighting, text-to-speech and Calibre-server problems.Read 15 Oct 2026 · github.com

Limit: support responsiveness

App Store reviews describe unanswered bug reports and certificate-related sync failures.Read 15 Oct 2026 · apps.apple.com

Limit: synchronization

Reviewers report that cross-device synchronization and account creation often fail, including after paying for the subscription.Read 15 Oct 2026 · justuseapp.com

Limit: update stagnation

Reviewers complain that the app has gone years without releases and fear it has been abandoned.Read 15 Oct 2026 · apps.apple.com

Maker and seller

The App Store identifies Konstantin Bukreev as the app's developer and seller.Read 7 Oct 2026 · apps.apple.com

Metadata and contents

KyBook extracts metadata automatically and lets users edit metadata and create or edit tables of contents.Read 15 Oct 2026 · apps.apple.com

Notable changelog

The February 4, 2019 release fixed Chinese OCR language-pack downloading and reading-time calculation issues.Read 15 Oct 2026 · github.com

OPDS

Users can browse built-in OPDS catalogs, add their own catalogs such as Calibre servers, and reach onion OPDS catalogs through Tor.Read 15 Oct 2026 · apps.apple.com

OPDS over Tor

The maker's page says the app supports .onion OPDS catalogs reachable via the Tor Network.Read 7 Oct 2026 · github.com

Other capabilities

The app can run a content server for accessing device files over Wi-Fi and supports streaming audiobooks from cloud storage.Read 7 Oct 2026 · github.com

PDF and DjVu tools

PDF and DjVu support includes manual or automatic margin cropping, double-tap zoom, PDF reflow on iPhone and OCR.Read 15 Oct 2026 · apps.apple.com

Praise: customization

JustUseApp reviewers repeatedly praise the large amount of customization and broad format support.Read 15 Oct 2026 · justuseapp.com

Praise: format breadth

An independent comparison describes KyBook 3 as supporting many formats, OPDS catalogs, dark mode and multiple page-turn styles.Read 15 Oct 2026 · assets-global.website-files.com

Praise: library management

An App Store reviewer highlights folder-based library organization as unusually easy and intuitive.Read 15 Oct 2026 · apps.apple.com

Privacy disclosure

Apple reports that the developer has not supplied privacy-practice details for the app.Read 15 Oct 2026 · apps.apple.com

Pro features

The maker's page lists DjVu, user dictionaries, multi-tab interface, content server, customizable themes, auto scrolling, PDF reflow and Tor network among Pro mode features requiring an in-app purchase.Read 7 Oct 2026 · github.com

Rating on Apple App Store

4.7 out of 5 from 4.7K ratingsRead 15 Oct 2026 · apps.apple.com

Rating on Appsrankings

4.6 out of 5 from 4,304 ratingsRead 15 Oct 2026 · appsrankings.com

Rating on JustUseApp

4.7 out of 5 from 24 reviewsRead 15 Oct 2026 · justuseapp.com

Reading controls

Reading modes include day/night/sepia themes, scrolling, curl or slide page turns, auto-scroll and text-to-speech.Read 15 Oct 2026 · apps.apple.com

Reading tools

Reading options include day, night and sepia themes, scroll, curl and slide page turns, auto scrolling and text-to-speech.Read 7 Oct 2026 · github.com

Release information

The maker's page lists KyBook 3 version 0.7.5 as released on February 04, 2019.Read 7 Oct 2026 · github.com

Self-hosting

KyBook can connect to self-managed OPDS/Calibre content servers, SMB shares and WebDAV, but the app itself is not documented as self-hostable.Read 15 Oct 2026 · github.com

Storage integrations

Storage options include local files, iCloud Drive, Google Drive, OneDrive, Dropbox, Yandex Disk, SMB/CIFS shares and WebDAV.Read 15 Oct 2026 · apps.apple.com

Summaries

A built-in summary editor supports Markdown and exports summaries in Markdown, HTML, PDF or RTF.Read 15 Oct 2026 · apps.apple.com

Supported formats

The app reads DRM-free EPUB and PDF, MOBI/AZW3, DjVu, FB2, CBR/CBZ/CBT, MP3/M4A/M4B, TXT and RTF.Read 15 Oct 2026 · apps.apple.com

Synchronization

Premium subscription synchronization covers ebook metadata, files, reading positions, bookmarks, annotations, reviews and summaries.Read 7 Oct 2026 · github.com

System requirements

The App Store requires iOS/iPadOS 11 or later; Mac use requires macOS 11 or later and an Apple M1-or-newer Mac.Read 15 Oct 2026 · apps.apple.com

Text tools

The app provides translation, dictionary lookups, custom Dictd/StarDict/Lingvo DSL dictionaries, regular-expression search and web/Wikipedia lookup.Read 15 Oct 2026 · apps.apple.com

Typography

EPUB, FB2 and MOBI readers allow font, size, margins, indentation, background and typography settings.Read 15 Oct 2026 · apps.apple.com

Plans and prices

Every KyBook 3 plan and price →

Strong points and limits

Who it suits

Verdict

Where Specifiction places it

• Ebook Reader Software#3 of 278.7