Comparison

duoBooks vs Readlang Language Readers

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

duoBooks

Read any book in any language with instant translation and detailed word explanations. Build your vocabulary with a personal dictionary and spaced repetition tools. Improve pronunciation with audio voiceovers and master new languages through immersive bilingual reading.

Highlights
  • Instant translation of any book
  • Personalized vocabulary dictionary
  • Spaced repetition for memorization
  • Audio voiceovers for pronunciation
  • Bilingual parallel text reading
  • EPUB reader for custom files
Features
Read full description

Read any book in any language with instant translation into your native language. We offer short stories designed specifically for beginner language learners. Alternatively, you can add any book from your device and read with translation whatever you want. Break any sentence into clear pieces and see every word explained in context. Instantly understand how the sentence works, what each word means, and how it fits into the full translation. In our app, you will also have your personal dictionary where you can keep your vocabulary in one place and easily review it whenever you want. Mastering correct pronunciation is key to language acquisition. In our app, you can listen to audio voiceovers of every sentence or word to hear it pronounced accurately. Immerse yourself in language learning with ease. To learn words, we provide a Spaced Repetition tool. With it you can review words at increasing intervals, ensuring long-term retention and mastery. Swipe through word flashcards effortlessly to build a robust vocabulary and make memorizing words a seamless part of your daily routine. Build your English vocabulary. Many people who are not native English speakers use our app as epub reader to read scientific materials or programming books in English. As long as you have an EPUB file for what you want to read, our app is the best choice. Our bilingual book reader is designed to enhance your language proficiency one page at a time. Practice and study foreign languages by reading parallel texts where every sentence is translated into your native language. Reading books with translation is a proven method for language learners to improve their reading comprehension, expand their vocabulary, and gain a deeper understanding of grammar structures. Read with translation any EPUB ebook from your device, or choose from our library with 3000+ books and short stories. Reading enhances your creativity, imagination, and empathy. Moreover, reading has been shown to reduce stress, improve mental health, and increase our overall well-being. Dive into a world of dual-language storytelling. Don't just take our word for it - hear what our users have to say: "This app has revolutionized my language study! I use it with my own EPUB files in a language I am studying. The interface is intuitive. It's also very fast to use and provides a smooth experience during long reading sessions." Read in English, German, French, Spanish, Italian, or any other language, build your vocabulary, and improve your grammar skills. With our cross-language ebook reader, translate books on the fly and listen to voiceovers of any sentence or word in your book. Best bilingual reading app available. With duoBooks you will: - Take control of your language learning journey and achieve your goals faster and easier than ever before. - Improve speaking by listening to how words and phrases are pronounced correctly. - Easily incorporate reading into your daily routine and reap the numerous benefits of this powerful skill, all while you learn English (or other languages). - Read English books with translation (or Spanish, French, etc.) easily even if it's not your native language. - Study words with scientifically proven technique (Spaced repetition). Swipe word cards and enjoy the process. Smart Interval system is as effective for memorizing words as English lessons. duoBooks offers short stories specifically created for beginners. They use simple vocabulary, repetitive words, simple dialogues, and uncomplicated sentences. Alternatively, we have a vast selection of classic literature. From the works of Edgar Allan Poe to the novels of Jane Austen. With over 3000+ classic ebooks available and the ability to import your own files, you'll never run out of options to practice your language skills. Whether you're a beginner or an advanced learner, duoBooks is your app for language learning success. Start your journey today with our free language learning app!

About

Readlang Language Readers

Learn languages by reading content you enjoy. Tap any word for instant translation, save new vocabulary, and track your learning progress. Offers a free plan with daily limits and a premium subscription for unlimited access and advanced features.

Highlights
  • Instant word and phrase translation
  • Save and review translated words
  • Read websites and EPUB books
  • Vocabulary practice
  • Progress tracking
  • Distraction-free reading
Features
Read full description

Language readers for English, Spanish, French, German and Italian: read real books at your level and tap any word to see its translation right above it. Readlang turns reading into language practice. Pick a graded reader from A1 to C1, a classic novel or a short story, tap an unfamiliar word or a whole phrase, and keep reading. Every word you translate goes to your vocabulary, so you can review it later with flashcards and quick games. WHAT YOU CAN READ • Language readers by level, A1 to C1: easy stories, classics and full-length books in English, Spanish, French, German and Italian • Fresh articles picked for you from international news sites • Any website in the language you are learning: news, blogs, forums, encyclopedias • Audiobooks • Your own EPUB books (Premium) HOW IT WORKS • Tap a word to translate it in place, without leaving the page • Tap the first and last word of a phrase to translate the whole phrase at once • Translation runs on your device when the language pack is downloaded • Translated words are saved to your vocabulary: flashcards, a multiple-choice quiz and the Meteor Words game • Reading statistics show your progress day by day WHY LANGUAGE READERS WORK A graded language reader lets you finish a whole book at a level you can follow. You meet new words in context, see them again in the next chapter and remember them without drilling lists. Start with easy language readers and move up as reading gets comfortable. FREE AND PREMIUM • Free: 30 translations a day, the whole library of books and websites, basic reading statistics • Premium: unlimited translations, longer phrases, your own EPUB books and the multiple-choice vocabulary quiz This app is independent and is not affiliated with Readlang.com. SUBSCRIPTION Premium is available as an auto-renewable monthly or yearly subscription. Prices may vary by location and are shown in the app before purchase. Payment is charged to your Apple Account at confirmation of purchase. The subscription renews automatically unless auto-renew is turned off at least 24 hours before the end of the current period. You can manage or cancel it anytime in your Apple Account settings. Terms of Use: https://readlang-mobile.com/terms Privacy Policy: https://readlang-mobile.com/privacy Support: support@readlang-mobile.com

Screenshots

duoBooks4 screens
Readlang Language Readers4 screens

Verdict

The call

duoBooks and Readlang Language Readers both sit at 4.7 stars, but that hides the real split: 100% of Readlang Language Readers's written reviews are positive against 68% of duoBooks's. Readlang Language Readers also leads on update cadence (every 5 days vs every 2 weeks). duoBooks's advantage is ratings volume (56 vs 5) and iOS requirement (15.0 vs 18.0). On price, rating, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. duoBooks sells 11 in-app purchases, starting at $2.99 per month and Readlang Language Readers sells 3 in-app purchases, starting at $8.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.7 for duoBooks against 4.6 for Readlang Language Readers. That said, the two scores are not equally well evidenced: duoBooks has 56 ratings behind it against 5, so its average is the more settled of the two. Written reviews are what separate them: 68% of duoBooks's written reviews are positive against 100% of Readlang Language Readers's.

UpkeepUpdate frequency

duoBooks ships an update every 2 weeks, Readlang Language Readers every 5 days. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

Scorecard4 real differences · 6 level
duoBooks versus Readlang Language Readers: the parameters behind the verdict, then further details
ParameterduoBooksReadlang Language Readers
PriceFreeFree
Rating4.7 (56 ratings) — better4.6 (5 ratings)
Positive reviews68.4% of reviews100.0% of reviews — better
Number of ratings56 — better5
Update frequencyEvery 2 weeksEvery 5 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better18.0
Further details — not scored
Size53 MB64 MB
Age rating12+17+
DeveloperPlainProg LLCAlisher Fayzullaev

Customer experience

duoBooks

All ratings55 ratings
Positive94.5%
Neutral0.0%
Negative5.5%
Written reviews38 reviews
Positive68.4%
Neutral13.2%
Negative18.4%

Readlang Language Readers

All ratings5 ratings
Positive80.0%
Neutral20.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

11 purchases

duoBooks

Subscriptions5
  • Full Plan7 Days trial$2.991 Month
  • Full Plan3 Days trial$6.991 Month
  • Full Plan7 Days trial$17.991 Year
Show 2 more
  • 6 Month Full Plan3 Days trial$19.996 Months
  • Full Yearly Plan3 Days trial$29.991 Year
One-time6
  • War and Peace$0.99
  • Silver Blaze$0.99
  • On The River$0.99
Show 3 more
  • Clochette$0.99
  • The Fishing Hole$0.99
  • Alice in Wonderland$0.99
3 purchases

Readlang Language Readers

Subscriptions2
  • Readlang Premium Monthly$8.991 Month
  • Readlang Premium Yearly1 Year trial$59.991 Year
One-time1
  • Lifetime access$99.00

Questions

Is duoBooks free?
duoBooks is free to download, with in-app purchases available.
Is Readlang Language Readers free?
Readlang Language Readers is free to download, with in-app purchases available.
Which has better reviews, duoBooks or Readlang Language Readers?
duoBooks is rated higher. duoBooks averages 4.7 out of 5 from 56 ratings, while Readlang Language Readers averages 4.6 from 5 ratings.
Do duoBooks or Readlang Language Readers have ads?
Neither duoBooks nor Readlang Language Readers shows ads.
Which is updated more often, duoBooks or Readlang Language Readers?
duoBooks ships an update every 2 weeks, and Readlang Language Readers every 5 days. Most recently, duoBooks was updated on October 24, 2026 and Readlang Language Readers on October 25, 2026.

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