KOReader: Open-Source eBook Reader

Posted by charleshan 3/31/2025

KOReader: Open-Source eBook Reader(github.com)

420 points | 106 commentspage 3

dantondwa 4/1/2025|

I use it on my Kindle and I love it. I can use better and more dictionaries, the controls are ergonomic and customizable, I can easily override the font so that every ebook looks exactly the same. It supports epub and with it my Kindle is faster, the battery lasts longer and it supports dark mode on an old model while Amazon officially doesn’t. Amazing software all around!

mmooss 4/1/2025||

It says it focuses on e-ink screen integration. What are the unique challenges of e-ink screens for reading ebooks?

At least in the past, screen refresh was slower; the reflective, rather than luminescent screen changed contrast and color performance; resolution was well behind standard screens.

The first two seem easily solved; the third hard to mitigate beyond larger print and appropriate typefaces. What else?

jhot 4/1/2025||

I think the eink focus is mainly in the UI as it avoids scrolling in favor of pages and tabs.

carlosjobim 4/1/2025||

How long was it since you saw an e-ink screen the last time? Resolution has been excellent for a while now. Refresh is still slow, but that doesn't matter for reading books. Contrast is fine, but not comparable to other display types.

mmooss 4/1/2025||

How high is resolution? The example screenshots look pretty low.

carlosjobim 4/1/2025||

Depends on device, but retina quality I would say. You cannot see individual dots so text appears like high quality print. The example screenshots are high resolution, you have to click them.

mmooss 4/1/2025||

I think you're right about the screenshot resolution.

Something is wrong with the layout that makes it awkward for me to read. The word spacing, at least, seems awful. Look at the lines "meaning behind printed words ..." (near top) and "widely believed that ..." (near bottom) compared to the lines above and below them.

Maybe it's the full justification adjustment - the text in the box is much better. Even the dictionary popover has word spacing problems.

That's a big deal for reading long-form.

beAroundHere 4/1/2025||

I came across KOReader when I was trying to jailbreak my kindle. It's UI looked great on e-ink screen. And it handled almost all ebook formats properly.

Lately, I've used it on Android, and UI which is more suited for e-ink screens, look not so polished on phones, but that's just nitpicking. It's fully usable and keeps adding support for new platforms.

lucius_verus 4/1/2025|

It really shines on e-ink Android readers such as the tablets Boox makes. I almost exclusively use it on my Boox because the built-in reading app is terrible.

jtmoulia 4/1/2025||

I use a Kobo because its overdrive integration lets me read ebooks checked out from my county library.

I'd love to give KOReader a try -- does anyone know if it can be used with library books, via overdrive or another integration? A quick search indicates KOReader doesn't work with DRM books, but I'm curious if someone has a solution.

lucius_verus 4/1/2025|

Koreader doesn't integrate with overdrive, but it's trivially easy to install it on your Kobo alongside the Kobo OS. You can continue to use overdrive on your Kobo and also dip into koreader for the better PDF viewer etc.

bb88 4/1/2025||

I tried koreader on a kobo. I wouldn't call it trivially easy when I installed it last year, and I promptly uninstalled it and removed all the hacks so I could get back to a sane installation of the Kobo OS again.

I think maybe for a kindle it might be worth it, but the reality is for Kobo, it's probably more hassle than it's worth.

I found my time better spent setting up a calibre-web in a docker container and then having my kobo sync to that. And that was awesome.

Larrikin 4/1/2025|||

What's the issue you had? When you reboot or quit you're kicked back to regular Kobo and you open up Koreader through a menu option.

The Kobo OS is good enough for me to recommend it to family, there's nothing wrong with the iPod experience of uploading books.

But Koreader+Tailscale+Kavita OPDS is the best reading experience I've ever had.

bb88 4/1/2025||

I don't remember frankly, maybe something with the script, maybe something with KFMon. Lack of integration with the Kobo OS itself? Maybe it had to be rooted to install KFMon, but I was reading Koreader could just run inside nickel menu maybe? But yet the script installed KFMon?

Again, I don't remember. And whatever it was it's not worth me trying to reinstall it just to remember what it was, and then to uninstall it again.

BeetleB 4/1/2025||||

The installation instructions are a bit windy, so many people miss that there's a simple script that automates the install for you.

The one thing you have to watch out for : You need to return those scripts whenever Kobo has an update. You won't lose your data or anything but a standard Kobo update dialed disables Koreader

cyberpunk 4/1/2025|||

It’s two .tgz files extracted to / … how is that not trivially easy?

a-french-anon 4/1/2025||

It's certainly an incredible gem, but I do find it quite bloated in features. Which is why I plan on trying https://github.com/baskerville/plato one of these days, to see if it does everything I need.

dfxm12 4/1/2025|

Is it not easy enough to just ignore the features you don't need?

a-french-anon 4/1/2025||

Those mean a pretty cluttered UI, in my eyes.

Gormo 4/1/2025||

And what's wrong with a UI being "cluttered", especially if the alternative is that it fails to expose the software's full functionality?

ementally 4/1/2025||

Book Story on Android is a much more modern FOSS eBook reader and supports other formats too.

https://github.com/Acclorite/book-story

ajot 4/1/2025|

I've used CoolReader in the past, and recently suggested its sucesslr LxReader[0] to my partner, while I like the simplicity in MuPdf[1]. What do you think are the biggest advantages of Book Story? I might give it a try.

[0] https://gitlab.com/coolreader-ng/lxreader

[1] https://f-droid.org/en/packages/com.artifex.mupdf.viewer.app...

ementally 4/6/2025||

Thanks for sharing, this is the first time I hear about LxReader.

The UI is so good, from quick look on LxReader's play store page, the UI is a bit basic.

ajot 4/16/2025||

Thank you! I might give it a try to get some reading done on my phone

ValtteriL 4/1/2025||

My Kindle got hardly any use nowadays thanks to this gem.

Out of the box it's a bit hard to use. Love it after configuring intuitive gestures for navigation.

Especially love the frontlight switch that lets me read while helping my kid fall asleep.

themadturk 4/1/2025||

I like KOReader, but gave it up in favor of the default software on my Kobo Clara BW, mainly because of library navigation. I prefer to keep all my books on the device, but the only way to find them (as far as I can tell) is by author. I haven't had the time to go through my whole library to fix the author sort, and it became a real problem to find books I already possess that I want to read.

Fortunately I didn't delete KOReader, so all my setup is still there if I find a reason to go back.

locusofself 4/1/2025||

I'd like to try it, but I really don't want to brick my beloved Kindle Oasis second edition. It's not sold anymore, at least not in the US.

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