Local-first viewer for scanned & digital books

Make local reading of scanned and digital books
more comfortable, more free.

A local-first design that safely analyzes and renders book content on your device. Enjoy a refined Japanese-modern UI with voice and gesture navigation for stress-free reading.

Supported platforms
Android (available)iOS / iPadOS (coming soon)Windows (coming soon)
Real app screensUI viewer with screenshots
① Wood bookshelf
② List view

* Switch with one tap between a cover-based wood bookshelf and a list that shows size and reading %

Home (bookshelf & list)

Two shelf views to match your style

Switch with one tap between a warm “wood bookshelf” for browsing covers and a “list view” that clearly shows file size (MB), author, and reading progress (%).

Live reading progress: See progress at a glance with badges and bars
Clear file details: Author, size, and extension shown smartly
Series grouping: Keep multi-volume scanned sets tidy
* Demo content on screen: “Black Jack ni Yoroshiku” by Shuho Sato
CORE FEATURES

Four reasons people choose BOOK-BOOK Chagama

Thoughtful features for privacy-minded readers and self-scanned book users

Fully local-first design

Bookshelf data, reading history, OCR text, and voice data are all processed on device. No unintended uploads to the cloud.

Privacy-first · Offline-ready

Wide format support

Open major formats like ZIP, CBZ, RAR, CBR, PDF, EPUB, and TXT directly—no unzipping required before adding them to your shelf.

Direct archive import

Vosk offline voice control

Even offline, jump pages fast with commands like “go to page 100” or “skip 20 pages”—ideal when your hands are busy.

Powered by Vosk AI

3D curl & image correction

Paper-like 3D page turns plus contrast, brightness, and grayscale controls improve reading quality for scanned books.

Clarity + 3D rendering

Key Features

Designed for stress-free scanned-book reading

Smooth loading & smart prefetch

Background prefetch reduces wait time when turning pages or seeking—for a smoother reading flow.

Fast flip & two-finger swipe skip

Long-press for a rapid page preview like flipping paper. Two-finger swipe skips a set number of pages to reach your target faster.

Slideshow auto-advance

Automatically turn pages on a timer—great for art books, skimming documents, or hands-free reading.

Vosk hands-free voice nav

Beyond next/previous, say commands like “skip 10 pages” or “jump to page 100” and move by voice alone.

Display & contrast tuning

Darken faint scanned text, adjust margins, and tune brightness/contrast for comfortable reading.

Pattern-based title & volume sorting

Define your own filename rules (including regex patterns) to neatly organize titles and volumes.

Useful Tools

Even more helpful features

Reading statistics

Automatically track daily reading time and total pages read to understand your pace.

Handwriting & annotations

Write notes directly on pages—useful for study materials and reference books.

OCR search & text-to-speech

Extract text from image-based books on device for keyword search and audio playback.

* Text-to-speech depends on OCR accuracy; results may vary with image resolution and text quality.

Plans

Licenses & feature comparison

Basic viewing is free. Paid plans can also be purchased from My Page on the web.

Feature comparison by plan
Features
Free
Basic
Pro license
Paid
Basic Viewer / TOC & BookmarksPDF/image display, table of contents, bookmarks, reading history.
Slide AnimationAuto page advance with configurable timer.
Curl Animation3D page-curl effect like real paper.
Reading Direction / Spread / QualityReading direction, spread mode, image quality settings.
Basic Page Turn / PinchTap/swipe page turns and pinch zoom.
Password LockProtect your books with a password for privacy.
Cover change (Custom Thumbnail)Set cover from any page, local image, or web image.
Smart Book CoverAuto-find cover art from title/author and set it as the thumbnail.
Margin CropAuto or manual crop of white margins for larger text.
Long-press Fast FlipRapid page flipping via long-press gesture.
Two-finger SwipeCustom shortcuts via two-finger swipe gestures.
HandwritingPen and marker drawing on Canvas with stroke persistence.
Text-to-Speech (TTS)OS TTS engine for reading text aloud.
Voice Commands (Vosk)Hands-free control via microphone voice recognition.
On-device OCR (ML Kit)Extract text from images on-device.
OCR Full-text SearchKeyword search across OCR-extracted text.

FAQ

Frequently asked questions

Download the app

Start with the free version. Get it from the Google Play Store.