Custom firmware for Xteink X4 e-reader — custom fonts, flashcards, Bluetooth keyboard, and more.
CrossPet is a Vietnamese fork of CrossPoint Reader — open-source firmware for the Xteink X3 / X4 e-paper readers.
- Custom fonts from SD card — Drop
.binfonts into/fonts/, select in settings. Dual font model: primary + supplement for mixed scripts (e.g. Latin + CJK). Generate.binfiles at xteink.lakafior.com - Flashcards — SM-2 spaced repetition. Import
.csvdecks from SD card via in-app file picker - Bluetooth keyboard (beta) — Pair a BLE page turner or keyboard. Separate firmware build due to memory constraints
- EPUB 2/3 with images, CSS styling, and multi-language hyphenation
- XTC pre-rendered format (>2GB support) and TXT/Markdown
- 3 built-in fonts (Bookerly, Lexend, Bokerlam) + custom fonts from SD card
- 4 font sizes with anti-aliased grayscale rendering
- Font cache for faster page turns + silent next-chapter pre-indexing
- Auto page turn — 1-20 pages/min, configurable as power button action
- Bookmarks via long-press, reading stats & streaks
- Dark mode, 5 UI themes, fully customizable status bar
- 9 sleep screen modes — Clock, Reading Stats, Page Overlay, custom images, and more
- Focus mode — hides all extras, just you and your books
- KOReader Sync for cross-device progress
- 4 screen orientations with remappable buttons
- 9 power button actions per single/double/triple click
| App | Description |
|---|---|
| Flashcards | SM-2 spaced repetition with SD card deck import |
| Virtual Pet | Tamagotchi chicken — evolves with reading |
| Clock | Digital clock + lunar calendar |
| Weather | Open-Meteo (no account needed) |
| Pomodoro | Work/break timer |
| Sleep Image | 9 sleep screen modes with image picker |
| OPDS Browser | Browse & download from Calibre/OPDS |
| Games | Chess, Caro, Sudoku, Minesweeper, 2048 |
- WiFi file transfer from browser
- OPDS / Calibre library browsing
- KOReader Sync
- OTA firmware updates
- BLE keyboard (beta, separate build)
Pair a BLE page turner or keyboard. Available as a separate firmware download.
| Key | Reader | Menus |
|---|---|---|
| Arrow keys | Page turn | Navigate |
| Enter | Select | Select |
| Escape | Back | Back |
Supports: GameBrick V1/V2, Free2/Free3, Kobo Remote, generic HID.
BLE uses ~50KB RAM. The BLE build disables images and CSS to fit. WiFi and BLE share one radio — they can't run simultaneously.
- Connect X3/X4 via USB-C, wake the device
- Go to https://xteink.dve.al/ and flash
git clone --recursive https://github.com/trilwu/crosspet
pio run --target uploadpio run -e default # Standard build
pio run -e ble # Bluetooth build (beta)
pio run -e gh_release # Release build/fonts/ # Custom fonts (Xteink .bin format: FontName_size_WxH.bin)
/flashcard/ # Flashcard decks (.csv, imported via in-app file picker)
/sleep/ # Sleep screen images (PNG/BMP)
- Go to xteink.lakafior.com — the Xteink web font maker
- Upload a
.ttf/.otf, tune weight + anti-aliasing in the live preview - Click Convert to .BIN
- Rename to
FontName_size_WxH.bin— e.g.Lexend_38_33x39.bin(the firmware parses size + glyph box from the filename) - Copy into SD
/fonts/and reboot. The font appears in Settings → Font
Dual-font: pick a primary (e.g. Latin) and supplement (e.g. CJK) — mixed-script text renders correctly without glyph fallback gaps.
Decks are CSV files. Header row required:
card_id,front_content,back_content,sr_due,sr_interval,sr_ease
1,"What is 2+2?","4",,,
2,"Bonjour \ greeting \","Hello",,,
3,"Line one/nLine two","Back side",,,- SRS fields (
sr_due,sr_interval,sr_ease) — leave empty for new cards; the app fills them in on review - Hint syntax — wrap an optional hint inside
\ ... \infront_content(shown smaller/dimmer during review) - Newlines — encode as
/ninside a field - Max 500 cards per deck
Import: Put the .csv anywhere on the SD card → launch Flashcards app → Import → pick file. The app copies it into /flashcard/ and derives the deck name from the filename (my_deck.csv → my deck). Review settings (new cards/day, max reviews/day) live in the app's settings screen.
- Fork → branch → changes → PR
See contributing docs.
CrossPet Reader is not affiliated with Xteink. Based on CrossPoint Reader.