Comparison

duoBooks vs LelaAI

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

LelaAI

Learn new languages by reading articles, websites, and documents. Get instant word translations directly on the text and personalize your learning by hiding words you already know. Build your own vocabulary list and study offline.

Highlights
  • Save articles, websites, and documents
  • On-text word translations
  • Hide known word translations
  • Personalized vocabulary list
  • Multiple language support
  • Offline access
Features
Read full description

Introducing "Lela - Read & Learn" - the ultimate language learning and reading app that allows you to save articles, websites, and documents to read later, all while learning a new language. With our unique feature, you can easily understand and learn new vocabulary with translations of words shown directly on top of the text. Plus, if you already know a word, simply tap on it and it will not be shown again, tailoring your language learning experience to your specific needs. Our app features include: - Save articles, websites, and documents to read later - Translation of words directly on top of the text - Tap on known words to hide translations - Personalized vocabulary list - Multiple language support including: Spanish, French, German, Italian, Japanese, and more. - No-ads, so you can focus on your learning without interruptions - Offline support, allowing you to access your saved articles and vocabulary list without internet connection - Strict privacy policy, ensuring that your data will never be shared with third parties. In addition, "Read & Learn" offers a seamless and user-friendly interface that makes language learning fun and enjoyable. The app is designed to help you improve your language skills while keeping up with your reading, all in one place, without any distractions. Download "Read & Learn" today and start reading and learning on the go! "Lela - Read & Learn" adhere's to Apple Standard End User License Agreement: https://www.apple.com/legal/internet-services/itunes/ dev/stdeula/

Screenshots

duoBooks4 screens
LelaAI4 screens

Verdict

The call

The clearest difference is rating: duoBooks at 4.7 against LelaAI's 4.3. duoBooks also leads on ratings volume (59 vs 3) and iOS requirement (15.0 vs 26.0). On price, review sentiment, update cadence and ads 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 3 in-app purchases, starting at $6.99 per month and LelaAI sells 2 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

duoBooks holds the better App Store score, 4.7 against 4.3. That said, the two scores are not equally well evidenced: duoBooks has 59 ratings behind it against 3, so its average is the more settled of the two. Written reviews complicate that: 68% of duoBooks's written reviews are positive against 75% of LelaAI's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

duoBooks ships an update every 2 weeks, LelaAI every 8 days. Both last shipped on November 3, 2026.

Scorecard3 real differences · 7 level
duoBooks versus LelaAI: the parameters behind the verdict, then further details
ParameterduoBooksLelaAI
PriceFreeFree
Rating4.7 (59 ratings) — better4.3 (3 ratings)
Positive reviews68.4% of reviews75.0% of reviews — better
Number of ratings59 — better3
Update frequencyEvery 2 weeksEvery 8 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better26.0
Further details — not scored
Size53 MB8 MB
Age rating12+4+
DeveloperPlainProg LLCWorathiti Manosroi

Customer experience

duoBooks

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

LelaAI

All ratings3 ratings
Positive66.7%
Neutral33.3%
Negative0.0%
Written reviews4 reviews
Positive75.0%
Neutral25.0%
Negative0.0%

In-app purchases

3 purchases

duoBooks

Subscriptions3
  • Full Plan3 Days trial$6.991 Month
  • 6 Month Full Plan3 Days trial$19.996 Months
  • Full Yearly Plan3 Days trial$29.991 Year
2 purchases

LelaAI

Subscriptions2
  • Pro - monthly$0.991 Month
  • Pro - yearly$5.991 Year

Questions

Is duoBooks free?
duoBooks is free to download, with in-app purchases available.
Is LelaAI free?
LelaAI is free to download, with in-app purchases available.
Which has better reviews, duoBooks or LelaAI?
duoBooks is rated higher. duoBooks averages 4.7 out of 5 from 59 ratings, while LelaAI averages 4.3 from 3 ratings.
Do duoBooks or LelaAI have ads?
Neither duoBooks nor LelaAI shows ads.
Which is updated more often, duoBooks or LelaAI?
duoBooks ships an update every 2 weeks, and LelaAI every 8 days. Most recently, duoBooks was updated on November 3, 2026 and LelaAI on November 3, 2026.

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