https://www.duolingo.com/profile/meatcan

Using Duo as a visually-challenger person

Duo has been a big help to me and I’ve been here since 2014 or so. There are a ton of good things that Duo does but there are also some ways that Duo could change in order to better serve those of us with vision problems.

An important note upfront: there are many people with many different types and degrees of vision loss. In this post, I’m just addressing what works for me. Your mileage will vary. I’m really hoping that other Duo users with vision challenges will chime in here with their own experiences and suggestions. The more proposed solutions, the better Duo can be.

I’m 58 but have only experienced serious vision loss for roughly 10 years so, in some ways, I’m still adapting to new situations and challenges that arise in daily life. I’m also a landscape architect, so I know something about designing for people of various abilities. I use a white cane when I’m out of my house and I do read and use the computer, although I’m a very slow reader these days. I have used some assistive technology on my PC, namely ZoomText. The software can be super helpful, but it’s not always very good with foreign language text to speech. I should also note that my primary use of Duo is through the website on a PC although I do use my Kindle occasionally as well.

Here are some things I’d like Duo to think about, and possibly, implement: Dark screen mode. I know lots of Duo users have been asking for this for quite some time. For me, contrast is very important. The white screen background is often so bright that it causes too much glare for me to see stuff properly. I usually turn down the screen brightness, which unfortunately can result in making everything else less readable. When I read an e-book on my Kindle, I can easily switch to a night mode that gives me a black background with white fonts. The ability to adjust the contrast is quite beneficial to me.

Bolder fonts. The typical font Duo uses is somewhat wimpy. Some letters, like “l” or “i” tend to look quite similar at times. Having the ability to make the font bolder could help. Or having the ability to switch to a serif font could be helpful too.

Font size. The fonts are pretty small at times. Not a big deal on my Kindle as I can pinch zoom the screen easily enough. But on the PC it’s often a pain in the rear. I can zoom my screen but that results in a lot of scrolling to read the entire screen. That’s a hassle and slows me down even more.

Eliminate the “graying out.” Duo has recently, and oddly, begun a practice of graying out, or ghosting, the answers to a question after a user hits the “Check” button. It then becomes nearly impossible to read any of the words in the answer. I’d like to check my incorrect answer to see where I might have gone wrong but I just can’t make out the words anymore. I have no idea why Duo does this or thinks it’s a good idea but I wish they’d stop doing that.

So that’s probably enough to stimulate some constructive conversation. I really don’t want this to come off as sounding like a lot of complaining. Instead, I’m hoping Duo reads this and realizes that there are ways to improve their product for all users. I’m no web designer but many of the items listed above are not that technically difficult to implement. I do know, as a professional designer in a different field, that using the principles of Universal Design benefits not only those of us with challenges but ALL users. And that should lead to a better Duo.

I’d like to hear from others! Please add your thoughts here or even send me an email. I’ll leave my address here for a couple days before removing it. (tjs1060 at yahoo) Thanks to Kimberly for suggesting this post and congratulations to those who managed to read my ramblings to the end. Cheers!

July 24, 2019

83 Comments


https://www.duolingo.com/profile/Little_Tatws

It's important that Duolingo be accessible to everyone. Night mode alone would be the best step forward.

July 24, 2019

https://www.duolingo.com/profile/juliet569059

night mode is fine for those with slight visual impairment. but for a blind person to use this sight is torture. they need a stripped down version built with accessibilty in mind. screen readers cannot navigate these games

July 24, 2019

https://www.duolingo.com/profile/Little_Tatws

I'm certain. I'm also thinking about how the design team prefers form over function and how long it'll take. A screen reader-friendly version would be excellent.

July 24, 2019

https://www.duolingo.com/profile/DanielVanD18

I support night mode, but maybe Duolingo wants to make everything for the majority who can see everything. Dark mode isn’t for blind or slightly blind people, it’s for everyone, no matter how good there sight is because the screen is WAY too bright!!

July 25, 2019

https://www.duolingo.com/profile/hoges.110

How do I get night mode L-T? Have been legally blind since a child. Now it's becoming almost too much of a struggle. Have thought of giving up Duo, but I can only say that during the dark times (no pun intended) Duo has literally saved my life. I will always be so grateful for it! :) I may find dark mode unsuitable, but it's worth a try!

July 24, 2019

https://www.duolingo.com/profile/thxndr

Here's a link to a post on how to get a dark mode, since I don't know how to explain it: https://forum.duolingo.com/comment/32321871 I use it a lot even though my vision isn't impaired :)

July 25, 2019

https://www.duolingo.com/profile/hoges.110

Thank you! :)

July 26, 2019

https://www.duolingo.com/profile/Lightning_11

Here is a post about how to Night Mode. I got night mode here and it is great.

Also, if you use Chrome, here is a link to my favorite night mode addon. I hope this helps.

July 25, 2019

https://www.duolingo.com/profile/hoges.110

Re:Lightning_11 Thank you! :)

July 25, 2019

https://www.duolingo.com/profile/hoges.110

Lightning_11 If I install this, does absolutely everything turn to night mode, or just the App/Duo website? Thanks!

July 26, 2019

https://www.duolingo.com/profile/oosix_

All of the addons Lightning_11 linked will put every website in dark mode.

If you want just Duolingo in dark mode, the post thxndr linked works.

July 27, 2019

https://www.duolingo.com/profile/hoges.110

Thank you!

July 27, 2019

https://www.duolingo.com/profile/uphilldweller

The thing I've personally always struggled with is spotting í as opposed to i (accented characters in general). I agree about the graying out being a nuisance.

July 24, 2019

https://www.duolingo.com/profile/n35w101

So glad you decided to make this post :-). Great suggestions.

July 24, 2019

https://www.duolingo.com/profile/meatcan

n35w101, thanks for the motivation.

July 24, 2019

https://www.duolingo.com/profile/juliet569059

The accessibility issues here have been discussed for years. It’s now worse

July 24, 2019

https://www.duolingo.com/profile/F.Huey

It sucks.

July 24, 2019

https://www.duolingo.com/profile/A_Sesquipedalian

A suggestion: could Duolingo have the option of choosing between the graphics of the different versions that they’ve had (along with night mode: this is a very good idea, and quite possibly the most suggested concept on the forum)? That way, they can offer versions from a time when the font was clearer whilst still attracting people who like the more modern style and appealing to the people who don’t like the new graphics. If each style was for, for example, 100 lingots, it could also appeal to people who feel that there aren’t enough items in the shop.

At a side note, the capital i and lowercase L are far too similar, not to mention language-specific letters. I agree that this should be changed.

July 24, 2019

https://www.duolingo.com/profile/uphilldweller

"...could Duolingo have the option of choosing..?"

I think this would be a helpful change in design philosophy.

July 24, 2019

https://www.duolingo.com/profile/hoges.110

It's amazing how many people are coming out of the woodwork now and sharing their difficulties. It makes Duo a safe spot not to be perfect. I nearly gave up due to bereavement and illness one time. Thomas Heiss literally got me through it. I'll always love him for that! He made sure 'Surfer Girl' (me) even got surfing videos!!

July 24, 2019

https://www.duolingo.com/profile/meatcan

suellen007, thanks for adding your experience and comments. That's what makes this place so good.

July 25, 2019

https://www.duolingo.com/profile/hoges.110

Thanks meatcan! :)

July 25, 2019

https://www.duolingo.com/profile/testmoogle

I like the way Kanji Garden does it, where they have a neat feature on the settings page allowing the user to pick the theme both on their website and in their mobile apps — "light", "dark", or "black" — and it instantly takes effect with a nifty transition animation.

Would be great if Duolingo had something similar. ^^

July 26, 2019

https://www.duolingo.com/profile/hoges.110

☆ Oooohhh! That sounds good! Pity I don't learn Japanese.... :(

July 26, 2019

https://www.duolingo.com/profile/ladyofscience

2 bird 1 stone. I like it! Take a lingot!

July 24, 2019

https://www.duolingo.com/profile/mothmanluv

The only problem is that you don't wanna have to make people work for/pay for a style that they'd need to use the site/app easier. :O So long as it's not anything in that regard, and just some fun colors and stuff, then it'd be pretty fun to buy them and use them. :)

July 25, 2019

https://www.duolingo.com/profile/4m4ter4su

Not blind but the option for dark mode is honestly a great way forward for autistic people as well, since it's easier on the eyes. Hell, add the option for pastel backgrounds for those who are dyslexic or have other forms of autism since some people can engage better with content that is easier on the eyes, which white often isn't.

Bold font options would also be very helpful as well as Font size and even font options for autistic/dyslexic people since this font does mix up "i"'s and "l"'s unintentionally and that isn't ideal for autistic learners who require certain font's to actually read/understand the text. Hope my insight helps. :)

July 25, 2019

https://www.duolingo.com/profile/hoges.110

☆ You really sound like you know what you are talking about! I've tried all the background colours and fonts - sometimes a particular combination will be quite soothing. At other times, I need a different set. Sometimes people innocently say, "Why don't you just make it bigger! But there are a lot of different factors involved. Sometimes BIGGER can destroy focus. Good to hear autistic/dyslexic can be helped with colour and font.

July 25, 2019

https://www.duolingo.com/profile/meatcan

suellen007, that's an excellent point! It often seems to me that the first reaction I get from full-sighted individuals is "just make it bigger." Magnification is not always the solution though!
I have a very limited field of vision so magnifying things often is totally useless.

July 25, 2019

https://www.duolingo.com/profile/hoges.110

If only BIGGER changed everything. Or else people say, "Why don't you just get stronger glasses!? There would be no blind people if this were the solution! I guess until you can't see everything 'looks' very simple.

July 25, 2019

https://www.duolingo.com/profile/meatcan

I wish I could hit the Upvote button a thousand times!

July 25, 2019

https://www.duolingo.com/profile/hoges.110

Haha! You're so funny meatcan!

July 25, 2019

https://www.duolingo.com/profile/xMira_

Just a question-- when you said pastel, it made me wonder: would a cream-colored background have the same benefit? I know my sudoku app (lol totally off-topic probably) has a cream with black font setting, a white with navy blue font setting, and a black with white font setting, (If I remember right) would that sort of thing work for Duolingo, do you think? And have the same benefits as a pastel background? I know my eyes hurt a lot whenever I look at white for too long so I usually have cream as my setting, let alone I love cream as a color. Thanks! :)

July 25, 2019

https://www.duolingo.com/profile/4m4ter4su

That's a great question! I use cream in my sudoku app myself too because it helps me concentrate on my 'game' and I also prefer cream paper over white paper when I was in college because it helped me engage more with the content I was learning. I think letting others have autonomy to bring in suggestions or to pick their own page colours could really help, even if it's a cream background!

July 30, 2019

https://www.duolingo.com/profile/meatcan

xMira, everyone has different preferences for background screen color but I could use an off-white, like cream, along with black text for high contrast. Not sure other pastels would work for everyone but thanks for adding your thoughts!
Salut !

July 26, 2019

https://www.duolingo.com/profile/Kelvin401862

Thanks for giving this very important feedback, it helps us all to understand what it is like to walk in your shoes.

July 24, 2019

https://www.duolingo.com/profile/ZiggyDeeee

Great suggestions! I'd love if Duolingo had a night mode, and making the site more accessible for those with any sort of vision problems would be really great.

July 24, 2019

https://www.duolingo.com/profile/s456976

Those night mode add-ons seem to be a solution to the night mode request.

Here are some ideas to change fonts and colors, and a way to get the text out of the grayed-out areas. I am using a Firefox browser on a desktop computer.


Fonts and Colors

To change fonts and colors I had to edit the style sheets (CSS).

  1. One idea is to add a permanent rule for the duolingo domain to a stylesheet called 'userContent.css' in your Firefox profile folder. (If afraid that this might break too much, proceed to 2.) Let's start with changing the font from 'din-round, sans-serif' to 'serif'

    • Enter 'about:support' to go to your browser's Troubleshooting Information page.

    • Open the Profile Directory

    • Create a 'chrome' folder there

    • Create a file called 'userContent.css' in the 'chrome' folder

    • For starters, edit 'userContent.css' to include a very blunt rule:

    @-moz-document domain("duolingo.com") { * { font: 18pt serif !important; } }

    • Save 'userContent.css' to disk

    • Restart the browser

    • Go to Duolingo

    • (Repeat edit-save-restart if necessary to change fonts and colors. Use the 'Inspector' tool to find out what you want to change.)

  2. The other idea is to edit Duolingo's style sheets, save a personal copy to your computer, and load it again for the next session. The browser's 'Inspector' and 'Style Editor' are very nice tools.

    Edit 5

    How to change the fonts in Duo's style sheets:

    There is a CSS universal selector section (*) in the current style sheets:

    • 'ltr-c93e7bca.css' (for the lessons; line 1232)
    • 'ltr-d9ff0477.css' (for the discussion board; line 1241)

    Change font-family from 'din-round,sans-serif' to 'serif'.

    (I'll add more information if anyone is interested.)


Text Areas

How to get the text out of the grayed-out text area using the browser's console and JavaScript:

  1. Optional: use 'Inspect Element' to get more information about a certain part of the web page using the 'Inspector' tool. Most text areas seem to start with '._2MGCg'.
  2. Open the 'Web Console' and type

    document.querySelector("._2MGCg").innerHTML;

(Hit Enter/Return to get the result.)

The console has a night mode, the text is scalable, and the text should be accessible to screen readers (not sure, but curious to know whether it works).

Edit 4

How to re-enable a text area:

  • For text areas that match 'document.querySelector("._2MGCg")'
  • Open the 'Web Console' and type

    document.querySelector("._2MGCg").disabled = false;

(Hit Enter/Return)


  • Edit 1, 2: Sorry, trying to get the formatting right.
  • Edit 3: added a closing curly brace to the 'userContent.css' code example.
  • Edit 4: how to re-enable a grayed-out text area.
  • Edit 5: how to change the fonts in Duo's style sheets.
July 25, 2019

https://www.duolingo.com/profile/landersflanders

Thanks lovey! I'll screen shot this and maybe some bright spark can do it for me. You've certainly put a lot of effort in here!

July 26, 2019

https://www.duolingo.com/profile/Lightning_11

Here is a post about how to Night Mode. I got night mode here and it is great.

Also, if you use Chrome, here is a link to my favorite night mode addon. I hope this helps.

July 25, 2019

https://www.duolingo.com/profile/hoges.110

You're amazing Lightning! Thanks! :))

July 25, 2019

https://www.duolingo.com/profile/Rob_Xaos

Bolder fonts. The typical font Duo uses is somewhat wimpy. Some letters, like “l” or “i” tend to look quite similar at times. Having the ability to make the font bolder could help. Or having the ability to switch to a serif font could be helpful too.

As someone with a different disability (dyslexia) the critical thing here is user choice. The current font Duo uses is one of the better san-serif fonts for those with dyslexia.

Perhaps DL could consider a range of font selection including font size?Understandably this can cause issues in a mobile app with limited screen real estate, but for the browser version it should not be too challenging to implement.

July 26, 2019

https://www.duolingo.com/profile/Je_suis_ZiggyD

Great post, I hope some -or all- of these ideas are used!

July 24, 2019

https://www.duolingo.com/profile/miaou-meow

aye, mate! :D please, don't think you are having these problems because of your sight only, i'm 25 and my sight is good, still i fully understand and support each of your items because i have the same troubles with them, too ♡ thank you for this post, friend :)

July 25, 2019

https://www.duolingo.com/profile/meatcan

wow, thanks everyone for pitching in and adding all your ideas and comments!

Special thanks to all of you who have shared their experiences, whether fully-sighted or visually-challenged. By exchanging and sharing ideas we ALL benefit.

LOTS of good stuff going on here. I hope this post continues to grow and expand.

July 26, 2019

https://www.duolingo.com/profile/hoges.110

Driving everyone crazy, meatcan!

July 26, 2019

https://www.duolingo.com/profile/lukazayd

I'd also wish they added more pictures where they can so we can visually learn, memorize and put the words into context. I'd feel that'll greatly increase the learning experience.

July 26, 2019

https://www.duolingo.com/profile/JayPhair

Thanks for sharing! I don't even have diagnosed visual impairment but have had the exact same issues as you. I think it's something we need to keep reminding them of so they know it is important to have an inclusive and universally accessible app.

At night example, I don't want to open my phone and see a screaming white light in my eyes.... it's crazy because you're supposed to practice languages before going to bed! Night mode, larger text pretty much everywhere, and make the corrections more visible would all be excellent modifications.

July 26, 2019

https://www.duolingo.com/profile/Lightning_11

I wish duolingo would PLEASE make it a practice to add settings, not changes. That way people who don't like what the updates are doing (if they exist) don't get messed up.

July 26, 2019

https://www.duolingo.com/profile/hoges.110

Totally. Let alone staring at a huge computer, trying to do research for a course when you can barely open your eyes. What I can't work out, is why others don't believe you. Using the phone for Duo is such a pain when you want to eagerly get stuck into learning languages for a while. Instead, I just have to whizz through, barely looking at the screen. Night mode - here I come! Except obviously someone else is going to have to install it. I can't stare at the screen, reading all those instructions!

July 26, 2019

https://www.duolingo.com/profile/SSarantos

The silver/light grey text on white background is wretched. It's not like they are paying extra for ink. Just make the text black so we can see it. With French it is near impossible to distinguish the accents over the letters.

July 27, 2019

https://www.duolingo.com/profile/daal39
  • 1390

I just logged on to make a similar request. I am studying some languages that do not use the latin alphabet, and my vision isn't so great either. Particularly when one is learning to distinguish the unfamiliar letters or characters, it is important to be able to see them clearly. Please make it possible for users to adjust the font size and allow us to customize the interface so that it suits individual needs. If we can't see the words well, we can't learn them well!

July 27, 2019

https://www.duolingo.com/profile/SSarantos

Most of my errors are due to the text issues and visibility.

July 27, 2019

https://www.duolingo.com/profile/schokolade

I can see fine and can't read the greyed out text after submitting my answer either. It seems counterproductive to stop people from being able to learn from their mistakes...

I know I'm wishing for too much, given that Duolingo won't even add one night mode, but I'd really like to see multiple day/night modes. Too much contrast hurts my eyes and can trigger headaches, so I tend to prefer dark grey on light grey in bright surroundings and off-white on dark grey in dim surroundings. Being able to choose between day/night and high/low contrast would be amazing.

July 25, 2019

https://www.duolingo.com/profile/Lightning_11

You are probably right about asking for too much. The staff can't handle a night mode or even adding one more item to the lingot shop. Just one!

Oh well, that is my personal gripe I guess... Maybe my post with about 30 new items overwhelmed them, if they checked it at all.

July 25, 2019

https://www.duolingo.com/profile/hoges.110

schokolade: Consistent migraine sufferer here...

July 25, 2019

https://www.duolingo.com/profile/cathyhevey

A night mode is a great idea!

July 25, 2019

https://www.duolingo.com/profile/meatcan

you know what's strange?
a website that uses an OWL for its logo but doesn't like to use a night mode!

July 25, 2019

https://www.duolingo.com/profile/hoges.110

Haha! He seems to be able to see no matter what! Maybe green is his colour of choice when it comes to his sight.

July 25, 2019

https://www.duolingo.com/profile/Grammy866114

I too have low vision my struggle is with new words being displayed in light orange on a white background .. maybe this could be changed to a stronger contrast in bold? :)

July 25, 2019

https://www.duolingo.com/profile/Denise777488

White is not the best background for many people with reading difficulties and is something worth Duo investigating. I also find the greying out annoying, I also like to see where I went wrong. Thank you for taking the time to share your experiences.

July 25, 2019

https://www.duolingo.com/profile/ARCANA-MVSA

I can totally see where you're coming from. My vision is perfectly fine, but I still use a Night Mode mimic, and DL ghosting the answers makes them hard to read, even for me.

Things to try:

  1. Install Stylus on your Chrome browser and search for styles for Duolingo. You'll find quite a few dark mode mimics. Just note: you may need to turn it off for some functions on DL, such as submitting a bug report or searching in the incubator (font turns white and text background stays white). For lessons, stories, and practice, the dark mode works just fine.

  2. Highlight the ghosted text and copy-paste into a different document where you can alter the text to see it better. It takes longer, I know, but it works. Or maybe even simply highlighting it can provide enough contrast to see it better.

Hopefully DL will finally actually listen to its users and implement at least a dark mode. Considering all the versions that already exist, it can't be that hard. But I understand where you're coming from, and I agree.

Knowing DL, we'll be waiting a long time before we see anything like an official dark mode, or indeed any kind of change in that direction. Just hang in there for the time being, and good luck.

Volgav vitsenanieff nivya kevach varatsach.

July 25, 2019

https://www.duolingo.com/profile/Meir_Eitan

Can I use duolingo on my kindle?

July 25, 2019

https://www.duolingo.com/profile/meatcan

Meir, you absolutely can use your Kindle for Duo!
However, don't bother using the Duo app, even if you can find it. It's no longer supported and very out of date. You can use the Silk browser to access the Duo website. I do it all the time and it seems to work pretty well. Good luck!

July 26, 2019

https://www.duolingo.com/profile/hoges.110

Never heard of Silk browser...

July 26, 2019

https://www.duolingo.com/profile/meatcan

suellen, it's the internet browser used by the Kindle.

July 26, 2019

https://www.duolingo.com/profile/hoges.110

Re: Meatcan Thanks! Sorry, Didn'see you post earlier!

July 27, 2019

https://www.duolingo.com/profile/hoges.110

Hi Meir! Apparently you can. There's a vision impaired person on Duo, his name was something like Philpot. He was brilliant using all the technology he had - and he had a lot!

July 25, 2019

https://www.duolingo.com/profile/diogomoraes_idp2

I loved the night mode idea

July 25, 2019

https://www.duolingo.com/profile/Bryce.F.R

I think that is a great idea, meatcan. The bright white screen, in the dark, can definitely strain your eyes. Your right about the font letters it can be confusing at sometimes, and I even got some questions wrong because I couldn't read the word properly.

meatcan, I feel your pain, being part-blind isn't easy and I understand. I am happy to support your ideas!

July 26, 2019

https://www.duolingo.com/profile/PatchyPatchy

I would love a dark mode, but understand if Duolingo needs time to adjust graphics. Many people have asked for dark mode so I feel Duolingo would do this soon. What I would like more is larger fonts! I have "Dynamic Text" on my devices but it gets hard when accents look like the same little dots, and I'm not even blind! Thank you for the post.

July 25, 2019

https://www.duolingo.com/profile/Bunnyee_

As a person who is very sensitive to the light, I can understand the need for dark mode. So I use an application on chrome called Dark Reader. It takes a minute to understand the toggles on how to get dark mode on only some of the websites that you use and not all, but overall, I use it all the time for sites that still have a defying white background. One day I hope Duolingo adds a dark mode setting, but for now, this does the job.

July 25, 2019

https://www.duolingo.com/profile/slogger

Agreed. For me, increasing the size of the font significantly or changing the font so that ,for instance, "t's" don't look like "l's" would help most.

July 25, 2019

https://www.duolingo.com/profile/MikeNolan6

The US Government has never defined what makes a website ADA-compliant. (They gave up on the project a couple of years ago.)

As a result, it may be up to the courts to decide what ADA compliance means on the web in the USA. I don't know what rules the EU has.

The downside of this is that the only way a site will know if they're not compliant is to be sued.

July 25, 2019

https://www.duolingo.com/profile/MelindaHep

A loud "amen" to everything you have said here! My vision is around 20/200 and I'm extremely light sensetive. You ade every point I'd thought of, but I'm going to give this more thought over the net few days/

July 25, 2019

https://www.duolingo.com/profile/hoges.110

MelindaHep: The light is a huge issue for me too. If it's bright, it puts such pain into my eyes. In my case, I don't know why ophthalmologists and optometrists can't get there heads around this. Have had some frightful experiences with them.

July 25, 2019

https://www.duolingo.com/profile/BaiShann

My eyesight is lessening too. I agree with everything the original poster said. In addition, I would add that I cannot read dark colour on lighter colour. Ever. So the corrections, red on red, are useless to me. Enlarging the screen does not help.

July 27, 2019

https://www.duolingo.com/profile/kimjongjung

In settings they should add a section for THEME & APPEARANCE, in which they should provide options to switch to dark mode, font size slider, using of custom fonts, etc. I use a browser extension "Dark Reader" on my Firefox for pc.

July 27, 2019

https://www.duolingo.com/profile/Meir_Eitan

You mentioned duo on your kindle, can I use duolingo on my kindle??

July 25, 2019

https://www.duolingo.com/profile/Thomas.Heiss

@Meir_Eitan

Quote: Can I use duolingo on my kindle?

Have you tried the Silk browser?

The new Duo full desktop or mobile website (UI updates) might be as buggy on that seldom plattform as other users have reported about the Safari browser incompatibilities.

But try it for yourself.

For the mobile app:

You need to sideload the official Android Duolingo app with the Google Play store.

AFAIK the Duolingo Kindle app is not supported anymore and was removed from the Kindle store.

Sorry, I do not own that device so I can't assist with specific technical informations.

But a search engine keyword for "Kindle Duolingo sideloading" should show you all the detail infos from the geeks - I am sure you can find some blogs writing about it in more detail with step-by-step instructions.

July 25, 2019
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