CrossTwins

How the community firmware CrossTwins differs from this site's Korean firmware, and how to install it and switch back.

Describes CrossTwins 2.0.0 · Xteink X4 and X3

About CrossTwins

CrossTwins is made by a community developer (meat-holic). From 2.0.0 it puts CrossTwins features such as the Korean menus, user body fonts and recent-book progress on the home screen on top of upstream CrossPoint 2.0.0 final. It is not a port of the Korean firmware's source, so it is used in much the same way but the menus and fonts work differently. It boots with its own CrossTwins logo.

Boot screen (CrossTwins logo)

This site doesn't build CrossTwins; it only helps you install it. Report problems on the CrossTwins repository. Per the 2.0.0 release notes, Bluetooth page turner reconnection has not yet been checked on a real device.

Differences from the Korean firmware

	Korean firmware	CrossTwins
Made by	crosspoint-reader-ko (this site)	Community developer meat-holic
Code	Korean fork with upstream 2.0.0 merged in	CrossTwins features merged onto upstream 2.0.0 final
Book font	Pretendard 10pt built in; 14pt and other fonts from the SD card	Pretendard 10pt built in; other fonts and sizes from the SD card
SD card font format	.epdfont (one file per size, made with the font converter)	.cpfont (upstream format; the font converter's .cpfont tab makes it too)
Menu languages	Korean, English	Korean, English (Pretendard menu font)
Line spacing	Seven steps from 0% to +75%	110, 120, 130, 145, 160, 175%
Web flasher devices	X4, X3, X4 Pro, X4 Classic, Sticky, Paper Mono	X4, X3 (get images for other devices from the releases)
App partitions	Two 0x6A0000 slots; the flasher writes the partition table too	Two 0x640000 slots like stock; runs on the device's current layout
OTA updates	crosspoint-reader-ko releases	meat-holic/CrossTwins releases (per-device images)
Version format	2.0.0-ko.N	2.0.0

CrossTwins 2.0 highlights line spacing steps taken early from upstream PR #4174, recent-book progress and chapter on the home screen, two-line titles in the browser, home and library, natural sorting of file names (rev.1), TXT reading progress, an image slideshow, and an MS-DOS theme alongside Lyra. The upstream 2.0 reader menu (clippings, auto page turn, page QR, progress sync and more) is included too. The table follows CrossTwins v2.0.0 source and release and Korean firmware 2.0.0-ko.0.

Install and update

With the web flasher (USB)

Open the web flasher in Chrome or Edge and pick X4 or X3.
Further down, press Flash CrossTwins and choose the device connected over USB.
When it finishes, the device restarts into CrossTwins.

Later updates

Settings → System → Check for updates looks for the image for your device in the latest meat-holic/CrossTwins release. 2.0 candidates before 2.0.0-rc2.rev.2 looked at upstream CrossPoint releases instead, so if you are on one of those, flash once more from the web flasher. The web flasher picks up the latest full release when this site is redeployed.

The flasher leaves the device's partition table alone and writes CrossTwins into the unused app slot. The image fits both the Korean firmware layout (0x6A0000) and the stock layout (0x640000). Books and files on the SD card stay, but we haven't checked whether the two firmwares read each other's settings files.

Korean fonts

From 2.0 a Pretendard 10pt book font is built in, so Korean books open without adding a font. For another typeface or larger text, add a .cpfont and pick it on the Font tab of Settings → Reader → Text Settings. Size, line spacing and margins are on the Size and Layout tabs of the same screen.

Line spacing and margins on the Layout tab

Reading Demian with the RIDIBatang .cpfont

The book on screen is Demian in a public-domain Korean translation from Wikisource, made into an EPUB by EPUBGUIDE.NET (CC BY-NC-SA 4.0). RIDIBatang comes from the SD card zip attached to the CrossTwins 2.0.0-rc2 release, unpacked into /.fonts.

Download on the device: connect to Wi-Fi and pick a font in Settings → Reader → Manage Fonts.
Over file transfer: start file transfer on the device, open its web page in a browser, and upload .cpfont files on the Fonts tab.
With the SD card: copy font folders from the crosspoint-fonts repository, or .cpfont files made with the font converter, to /.fonts or /fonts, for example /.fonts/FontName/FontName_14.cpfont.

The Korean firmware's .epdfont files (such as KoPub Batang) don't work in CrossTwins, and CrossTwins' .cpfont files don't work in the Korean firmware. If you switch between them, keep fonts for each. The first 2.0 candidate (rc.ct.0) listed online font downloads as not working on the X3 and X4; if a download fails, use file transfer or the SD card.

Back to the Korean firmware

In the web flasher, pick your device and press Flash on the Korean firmware at the top.
The flasher writes the Korean firmware's partition table and app together. Books and .epdfont fonts on the SD card work again as before.

For settings and features, see the CrossTwins documentation.

Releases: changes and test coverage per version
SD card fonts: installing .cpfont and the folder layout
Report a problem: GitHub issues