E-INK PDF / COMIC VIEWER

InkPress User Manual

A quiet viewer for PDFs, comics, and scanned books, optimized for E-ink (electronic paper) devices such as BOOX. It suppresses ghosting and flicker so you can read calmly, just like paper.

Version 1.2.4 Requires Android 8.0 or later

This manual covers every feature. Use the Contents to jump straight to the topic you need.

01Supported files & devices 02Getting started (set up your library) 03Using the library 04Reading (reader controls) 05Layout settings 06E-ink optimization 07Annotations, bookmarks & notes 08Cloud sync (Dropbox) 09Home screen widget 10Settings 11Troubleshooting (FAQ)

Key features

Here are the actions you'll use most often. See each chapter for detailed steps.

Page turning

Tap the left or right side of the screen to move between pages. Right-to-left turning is also supported for comics.

Two-page spread

Show two pages side by side in landscape. Fix page alignment with a single tap.

Auto margin trimming

Automatically crops away the page margins so text and artwork appear larger.

Handwritten notes

Tap the pen icon to enter handwriting mode and write directly on the page.

Create folders

Drag one book onto another to group them into a folder.

Cloud sync

Link Dropbox to keep reading where you left off across multiple devices.

Supported files & devices

Supported formats: PDF / ZIP / CBZ / RAR / CBR / images (JPG, PNG, WEBP, BMP, GIF)
Supported devices: Android 8.0 or later. Optimized for E-ink devices such as BOOX/Onyx (also works on regular Android devices).
Encrypted PDFs can be opened by entering the password.

Getting started (set up your library)

On first launch, an onboarding tour (4 pages) appears: (1) Set up your library, (2) Reading & settings, (3) Bookmarks & notes, (4) Widgets. You can replay it later from "Settings → System & other → View onboarding."

STEP 1

Set up your library

STEP 2

Reading & settings

STEP 3

Bookmarks & notes

STEP 4

Widgets

Registering library folders

1Tap "Choose folder" on the empty screen, or go to "Settings → Library → Change library / Add library."
2Select a folder on your device that contains books (you can register multiple folders).
3Once registered, the books in the folder are scanned automatically and cover thumbnails are generated.

Using the library

Opening & finding books

Tap a book to open it. Tap a folder to go inside, and use the Home / Back buttons at the top or your device's back key to move around.
Resume the most recent book instantly from the "Recently read" card at the top of the screen (tap × to hide it).
Pull to refresh to rescan your library (it skips quickly if nothing in the folder has changed).

Sorting & organizing

Use the sort icon at the top to choose name (A-Z / Z-A), date (newest / oldest), or custom (manual).
Drag & drop: Long-press a book and drag to reorder. Drop one book onto another to create a folder (it switches to custom order automatically).
Multi-select: Long-press a book → "Select multiple" to act on several at once.

Per-book menu (long-press)

Long-press a book to access the following actions.

Reading settings (layout) Cover: choose page / crop Rename Info (file details) Remove from history Delete

About deleting

⚠ Note

The default "Delete" only hides the book from your library; the file itself remains. Hidden books can be restored from "Settings → Library → Manage hidden books."

If you want to delete the file itself, turn on permanent deletion in "Settings → Library" (it comes with a warning in red text; the library's root folder cannot be deleted).

Covers & file name display

Choose a cover size of small / medium / large (Settings → Library).
Showing the file name and extension below the thumbnail can be turned on/off independently.

Reading (reader controls)

The first time you open a book, an operation guide (a diagram of tap zones) for your reading direction is shown once.

Reader menu bar (tap the center to show it)

Sleep

Table of contents

Set as cover

Auto trim

Quick adjust

Book settings

Turning pages

Tapping

Horizontal (page-turn) mode … the left 30% and right 30% of the screen turn pages, and the center 40% = menu. In comic mode (right-to-left, the default), left = next and right = previous; in left-to-right mode, left = previous and right = next.
Vertical scroll mode … top 25% = previous, bottom 25% = next, center 50% = menu.

Next pageLeft 30%

MenuCenter 40%

Previous pageRight 30%

The diagram shows the default comic (right-to-left) mode assignment. The left and right 30% each turn pages, and the center 40% is the menu. In left-to-right mode this is reversed: left = previous, right = next, and in vertical scroll, top 25% = previous, bottom 25% = next, center 50% = menu.

Swipe: Swipe left/right (up/down in vertical mode) to turn pages (enable it in settings).
Volume buttons: Volume down = next, volume up = previous. You can reverse this in settings.

💡 Tip

You can read using only the power and volume buttons, which is very handy on E-ink devices.

Zoom & display

Pinch to zoom in and out (up to 4×), and double-tap to return to the full-page view (reset zoom).
Auto Crop: Detects the margins and zooms automatically to display text larger (via the reader's menu button).
Zoom / position lock: Fix the zoom level and position so every page is read within the same frame (handy for trimming margins on scanned books).
Quick adjust: Tune contrast, saturation, and monochrome on the spot while previewing the result.

Moving & navigation

Tap the center to show the top and bottom menu bars.
Table of contents (TOC): Jump from the PDF's TOC tab and the thumbnail list tab.
Jump to page number: Enter a number to go there.

Saving your progress

Your reading position is saved automatically when you switch apps or the screen turns off, so you can pick up where you left off next time (you can also have it open automatically on startup via "Settings → Reader → Resume last book").

Layout settings (per book & per folder)

Open these from the "Book settings" button inside the reader, or by long-pressing a book/folder in the library → "Reading settings / Folder settings."

Settings are inherited in the order folder → subfolder → book (priority: book > subfolder > parent folder). Use the "Make folder default / Apply to entire folder" buttons to set them in bulk.

Parent folder

›

Subfolder

›

Book

Priority Book > Subfolder > Parent

Setting	Details & options
Reading direction	Right-to-left (comics, default) / left-to-right / vertical scroll (webtoon)
Two-page spread	ON / OFF
Spread alignment fix	Switch the odd/even page pairing with one tap (e.g. whether to show the cover on its own)
Auto spread in landscape	Switch to a two-page spread automatically when you turn the device sideways (ON by default)
Offset by one page	Shift the spread forward or back by one page
Contrast	Adjust with a slider (sharpen faint text)
Saturation	Slider (for color E-ink)
Monochrome / dithering	Turn ON to convert to black and white (makes text sharper on standard E-ink)
Background color	Default / white / black
Rendering quality	High quality / performance
Zoom / position lock	ON / OFF
Reset	Book: clear the book's own settings and revert to the parent's settings / Folder: revert to the app defaults

E-ink optimization

These features make reading comfortable on E-ink (electronic paper) devices.

Full refresh (clear ghosting): On BOOX/Onyx devices, a GC16 hard flash wipes out ghosting completely (a soft flash on non-Onyx devices). In "Settings → Reader → E-ink refresh" you can choose OFF / auto / every 1, 3, or 5 pages.
Contrast adjustment & dithering: Sharpen faint text and convert images to E-ink-friendly black and white.
Rendering quality mode: Choose high quality or speed.
Sleep (screen off): Tap the moon icon at the top left of the reader to turn off the screen (lock the device). Useful on E-ink devices where the power button is hard to press.
BOOX stylus support: On BOOX devices, you can make handwritten annotations with the hardware pen.

🔒 About privacy

The sleep feature uses your device's Accessibility service and only works when you have enabled it. It never reads the screen contents, and no data is collected or sent.

Annotations, bookmarks & notes

There are 4 annotation tools: Navigate / Pen (handwriting) / Eraser / Lasso (range selection).

Navigate

Pen

Eraser

Lasso

Colored bookmarks

Colored bookmarks: Tap the bookmark zone → choose from 5 colors: red, blue, green, yellow, and purple (in a spread, the left/right page is detected).
Text notes: Leave a note at a position on the page, then edit or delete it.
Handwritten annotations (pen): Draw freehand. Adjust the pen color (5 colors) and thickness from the side toolbar.
Eraser & lasso: Erase your drawings, or select a range to move or delete it (size is adjustable).
Annotation list (within a book): List all of that book's bookmarks, notes, and handwriting, and jump to them.
All-annotations view (across books): From the annotation icon at the top of the library, view annotations from all your books across tabs (All / Bookmarks / Notes / Handwriting / History), with count badges. Links broken by moving folders, for example, can be restored with "Relink."
Export / import: Export and import all annotations, history, and covers as JSON (for moving to a new device; in "Settings → Library").

Cloud sync (Dropbox)

Carry your reading state across multiple devices (for example, your phone and an E-ink device).

Phone

⇄

Dropbox

⇄

E-ink device

Reading position = furthest read winsAnnotations & history = mergedLayout = newer wins

How to connect

Go to "Settings → Library → Cloud account → 'Connect to Dropbox'." Once connected, the progress sync and annotation sync toggles below become available (they are grayed out before connecting).

What gets synced

Item	How it works
Reading position	The furthest-read position wins (it never goes backward even if you move back). When you open the book on another device, a confirmation dialog says "The remote has read further" and lets you jump ahead (Kindle-style).
Layout settings	The newer one is applied quietly (spread, reading direction, zoom lock, etc.).
Annotations	Bookmarks, notes, and handwriting are each reconciled and merged. Deletions are propagated to other devices too.
Reading history	Merged (books read on another device appear in "Recently read").

Books are identified by file content, so they are treated as the same book even if the storage location differs from device to device.
Import from cloud: Pick a file on Dropbox, specify the destination library folder, and download it.
You can review your accounts in a list and disconnect them too (credentials are stored encrypted).

Cloud connection supports Dropbox only.

Home screen widget

Place one on your home screen to reach your books without opening the app (4 types).

Return to your most recent book with one tap.

Reading history

A list of recently read books.

Bookmarks

Jump to the relevant page from your bookmark list.

Combined widget

A combined display of all of the above.

You can adjust the widget's appearance in "Settings → Widgets" or on the setup screen when you place it: background transparency ON/OFF, opacity (0–100%), and text size (70–180%). The design stays easy to read on E-ink, too.

Settings

The settings screen has 3 tabs: Library / Reader / System & other.

Library

Manage library folders, show file names and extensions, cover size, permanent deletion, manage hidden books, cloud account plus progress/annotation sync, and annotation export/import

Reader

Rendering quality, E-ink refresh and interval, scroll direction (horizontal/vertical), default spread, auto spread in landscape, reverse volume buttons, swipe gestures, resume last book, reader background color, and app theme (light/dark/system)

System & other

Version info, replay onboarding, help, and a "Support the developer (Ko-fi)" link

Troubleshooting (FAQ)

My books don't show up

Check that a library folder is registered in "Settings → Library," then pull to refresh the library. Unsupported formats are not shown (→ Chapter 01).

The file remains after deleting / I don't want to delete it

The default delete only hides the book from your library. To remove it completely, turn on permanent deletion (→ Chapter 03). Hidden books can be restored from "Manage hidden books."

I can't continue reading on another device

Connect both devices to the same Dropbox and turn on progress sync (→ Chapter 08).

Ghosting remains on the screen

Set "E-ink refresh" to auto or a short interval (→ Chapter 06).

I can't turn off the screen (E-ink device)

Use the moon icon at the top left of the reader to sleep. The first time, you'll need to enable Accessibility (→ Chapter 06).

The text is faint / hard to read

In the book settings, raise the contrast, turn on monochrome (dithering), and enlarge with auto trim (→ Chapters 04 & 05).