CHESS GAME ! FOR EINK DISPLAYS - InkChess

[LukaAbdul]

📘 InkChess for Kobo Libra Colour
Hello and welcome!

For a long time, I was quite disappointed that there was no native chess game available on my Kobo Libra Colour—or on most e-ink readers, for that matter. I also tried PBChess, but it kept freezing and didn't work properly on my two Kobo devices.

After some tinkering, I discovered that Kobo's built-in web browser can open local HTML files. So I decided to build my own chess game!

♟️ What is InkChess?
InkChess is a full-featured two-player chess game that runs directly on your Kobo reader via the built-in browser. It includes:

Complete rule support (castling, en passant, promotion, etc.)

Save and load functionality for your last game

Clean, readable interface for e-ink screens

I’m sharing this project for free—but if you find it useful, please consider donating a coffee or any small token of support. Creating this wasn’t easy, especially given how outdated the Kobo browser is!

🔧 Installation Instructions
Download and unzip the InkChess folder.

Copy the unzipped folder into the .adds directory on your Kobo device.

To launch the game, open your Kobo browser and go to:

file:///mnt/onboard/.adds/InkChess/InkChess.html
For quicker access, bookmark it or set it as your home page.

📱 Optional (NickelMenu Integration)
If you’re using NickelMenu, you can add a shortcut directly to the main menu:

menu_item : main : InkChess : nickel_browser : file:///mnt/onboard/.adds/InkChess/InkChess.html
This allows you to launch the game with a single tap from the main screen.

⚠️ Note: The Kobo browser currently only opens when Wi-Fi is enabled. If anyone knows a workaround for this, please reach out—help is appreciated!

🛠️ Future Plans
If there's enough interest and support through donations, I’d love to expand InkChess into a full game platform for Kobo devices:

🧠 Play against the computer (AI support)

🌐 Local multiplayer over Wi-Fi

📚 Add move logs and analysis tools for training

If you enjoy InkChess and want to support further development, please consider donating.

💖 Support InkChess

InkChess was built with passion, late nights, and a deep love for both chess and open devices. If this little game brought joy to your Kobo, please consider giving back.

Even a small donation is a big “thank you” that helps fuel future improvements, new features, and open tools for all e-reader users.

Let’s prove that even the simplest devices can offer great experiences—together.

☕ Donate a coffee or more here:
https://www.paypal.com/donate/?busin...rency_code=EUR


Thank you—and enjoy your games!

Moderator Notice
Updated the attached file to the latest version

[Cootey]

Very cool. I’ll check it out. Thanks for the NM template.

[Tommalka]

Originally Posted by LukaAbdul

🌐 Local multiplayer over Wi-Fi

Is this even possible with the limited browser?

[LukaAbdul]

Hi everyone,

I noticed that I had mistakenly uploaded the wrong file in my original post, which externally referenced JavaScript. So it was not a local game Unfortunately, I'm unable to edit that initial post. ( Can someone help how to do this on this forum? )

Therefore, I'm creating this new post to share the updated file. This corrected version now properly uses a local reference to JavaScript and includes several exciting new options:

🧠 Play against the Computer: AI support has been integrated, allowing you to test your skills against a computer opponent.

🔄 Choose Your Color: You can now select whether to play as white or black.

✨ Enhanced E-Ink Experience: Animations and the overall interface have been further polished and optimized for e-ink screens.

Regarding Wi-Fi multiplayer, I'm actively working on implementing basic connectivity between players. The main challenge is ensuring compatibility across various Kindle and Kobo devices. I'm still figuring out the best approach for this, but I'm committed to making it work.

Thanks for your understanding!



🔧 Installation Instructions
Download and unzip the InkChess2.zip into the InkChess folder.

Copy the unzipped folder into the .adds directory on your Kobo device.

To launch the game, open your Kobo browser and go to:

file:///mnt/onboard/.adds/InkChess/InkChess.html
For quicker access, bookmark it or set it as your home page.

📱 Optional (NickelMenu Integration)
If you’re using NickelMenu, you can add a shortcut directly to the main menu:

menu_item : main : InkChess : nickel_browser : file:///mnt/onboard/.adds/InkChess/InkChess.html
This allows you to launch the game with a single tap from the main screen.

⚠️ Note: The Kobo browser currently only opens when Wi-Fi is enabled. If anyone knows a workaround for this, please reach out—help is appreciated!

🛠️ Future Plans
If there's enough interest and support through donations, I’d love to expand InkChess into a full game platform for Kobo devices:

🌐 Local multiplayer over Wi-Fi

📚 Add move logs and analysis tools for training

If you enjoy InkChess and want to support further development, please consider donating.

💖 Support InkChess

InkChess was built with passion, late nights, and a deep love for both chess and open devices. If this little game brought joy to your Kobo, please consider giving back.

Even a small donation is a big “thank you” that helps fuel future improvements, new features, and open tools for all e-reader users.

Let’s prove that even the simplest devices can offer great experiences—together.

☕ Donate a coffee or more here:
https://www.paypal.com/donate/?busin...rency_code=EUR

[LukaAbdul]

I have noticed a few potential issues that I'm currently trying to resolve. To get a better understanding of its performance on different devices, I'm looking for individuals who might be willing to test it on Kobos and Kindles. If you've had a chance to try it out, I would greatly appreciate any feedback you could share regarding your experience and anything you may have noticed.

Thank you
☕ Donate a coffee or more here:
https://www.paypal.com/donate/?busin...rency_code=EUR

[elaeoth]

Hello! Thanks for your work, it's very good, I really love the simplicity and the overall design.

Some things I didn't like:
1: The biggest problem is the fact that we can't play without internet, which is very sad. If I would love one change, it would definitely be that.

2: Sometimes, the reactivity is not on point, I need to do the move several times before it is recorded.

3: The screen refreshs too much, at each move. i don't know if it's mandatory, but the experience would be smoother if it refreshed less (Like every 5-10 moves, or even only between each game, I don't kow if it's doable, but that'd be the best)

4: The AI is really bad, I beat easilly the "Ludicrous" mode, and I'm not that good, haha.

But again, very nice! I love the way the pieces change side when you don't play an AI, it's a subtle, but very smart and good move, keep up the good work!

[framed]

This is great thanks! Working nicely on Kobo Libra H20. However, it would be great if it was more user friendly for B&W devices. In particular the red highlight when making a move is hard to see. Showing an outline would help.

[denilsonsa]

A chess game in a single HTML file (plus jQuery, plus static PNG images). Nice.

Have you published it at GitHub or some other online repository? What's the license? I believe it should be easy enough to remove the jQuery dependency.

Also, if you publish it online somewhere (e.g. using GitHubPages), it can be accessed by pointing the browser to the online website where you host it. If you do that, you could even considering adding a link to it from https://github.com/dajbelshaw/einklink

[LukaAbdul]

Hey everyone,

Sorry for the recent silence! Chess for E-Ink is a personal side project of mine, but I really appreciate all your feedback. Let me answer some of your recent questions and bug reports.

1: The biggest problem is the fact that we can't play without the internet.

This is a top priority, and I'm working on a solution. It's a tricky problem, especially for Kobo devices, which remain a mystery. Any help from the community on this would be greatly appreciated!

For now, you can play locally on all supported E-Ink devices except for Kobo.

Kobo Workaround: You can play locally on a Kobo, but you must be connected to a Wi-Fi hotspot. The hotspot itself does not need to have an active internet connection.

2: Sometimes, the reactivity is not on point; I need to do the move several times before it is recorded.

I've made some optimizations in the latest version that should improve this. The more testers I have, the better I can fine-tune the performance, so thank you for your feedback!

3: The screen refreshes too much at each move.

Screen refresh settings are a balancing act, as they behave differently across various devices. I'm trying to find a middle ground that works well for everyone. Again, the more feedback I get from different devices, the more I can optimize this.

4: The AI is really bad. I easily beat the "Ludicrous" mode, and I'm not that good, haha.

You're right! The AI has been updated in the new version to be more challenging, and I plan to improve it even more in the future.

5: The red highlight when making a move is hard to see.

Good point. This is being worked on. For now, the green and red highlights can be disabled in the settings. This will be properly optimized in version 10. The visibility is also related to the game's refresh rate, which I'm still improving.

Have you published it on GitHub? What's the license?

I haven't published it on GitHub yet, mainly because it's a personal side project. If there's enough community interest, I will definitely consider it! For now, the license is Freeware, meaning it's free to use indefinitely, but I retain all rights and control distribution. I plan to keep it that way.

Why not remove the jQuery dependency and host it online?

That's a great suggestion! The main reason I included jQuery locally was specifically to enable offline play on most devices. That was the original goal.

Announcing Version 8!

A lot has changed in this new version. Please give it a try!

What's new:

Save and load games

Game log/notation

General performance optimizations

The more testers I have and the more bugs you find, the more quickly I can make it better. Thank you for your support!


"To everyone who has donated, thank you from the bottom of my heart. Your support means the world to me, and every coffee truly motivates me to keep working on this project! ��"

☕ Donate a coffee or more here:
https://www.paypal.com/donate/?busin...rency_code=EUR

Happy playing,

[Ypetremann]

Nice work

Your work made me try to make other games the same way.
I wanted for a long time to add a game of Go that I can play with friends.

Here my finding/workings:
- The browser is equivalent to Android Browser 4 ("browserslist":["Android 4"])
- You can use Vite with @vitejs/plugin-legacy plugin
- Also can use Postcss with autoprefixer, postcss-preset-env and doiuse (to see unsuported css features)
- I made a quick devtool for Kobo browser at https://github.com/YPetremann/vite-plugin-eink-devtools (if you want you can add the script at https://github.com/YPetremann/vite-p.../src/script.js manually) It permit to see logs and when a crash occur, can't see parsing errors
- I made a quick and dirty 2048 clone https://github.com/YPetremann/Ink2048
- fetch is not present in this browser so I think we should try to use old XMLhttpRequest ...

What are my goals for now:
- if possible in any way: fullscreen web app
- window.close to return to home screen
- games: go, reversi
- utils: shopping list, dices

[Ypetremann]

also if I can make the browser not need internet, this could make a huge leap

[denilsonsa]

My suggestion about removing jQuery was to actually replace it with http://vanilla-js.com/ , because plain DOM manipulation doesn't need jQuery. That would make it smaller, with less overhead, and thus better for old devices.

I would even try to do that myself and send a patch, but I see a bunch of minified functions in the source-code. That makes me wonder if such functions were copy-pasted from another project or if they were written from scratch. And if they were copy-pasted, it makes me wonder about the license of the original source-code where it was copied from, and the license of your project as well. (And it's important to give credit to the original project too.)

I'm not accusing anyone, these are just questions that came to my mind.

[Ypetremann]

The main problem is that for most developper, vanilla-js is tedious and bulky, Also they need to think about browser compatibility, jquery was doing that for them.

On my side the reason I use vite with @vitejs/plugin-legacy is thaty I can write as I want, even in vanilla js but using modern features, the plugin check which feature it need a polyfill and transpile the code as needed

[Leonatus]

Copy the unzipped folder into the .adds directory on your Kobo device.

In my Kobo, there is no .adds directory. I created one at the root directory, but in the webbrowser it takes no effect. What did I do wrong?
Sorry, I'm not a technic!

[DNSB]

Originally Posted by Leonatus

In my Kobo, there is no .adds directory. I created one at the root directory, but in the webbrowser it takes no effect. What did I do wrong?
Sorry, I'm not a technic!

You created the .adds directory and then unzipped the InkChess archive folder into the .adds directory so you now see .adds/InkChess (you will likely have to rename the InkChess directory to remove the version number (i.e. Inkchess_v8 to Inkchess).

You then opened your Kobo's web browser and went to 'file:///mnt/onboard/.adds/InkChess/InkChess.html' (without the 's) and remember it is case sensitive and you need the 3 ///s after the file:.