# duoBooks vs Readlang Mobile

The clearest difference is review sentiment: Readlang Mobile at 100% against duoBooks's 69%. duoBooks's advantage is rating (4.7 vs 4.3) and ratings volume (48 vs 3). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. duoBooks sells 11 in-app purchases, starting at $2.99 per month and Readlang Mobile sells 2 in-app purchases, starting at $6.99 per month. Whichever you choose, the download price is not the number that matters.

duoBooks holds the better App Store score, 4.7 against 4.3. That said, the two scores are not equally well evidenced: duoBooks has 48 ratings behind it against 3, so its average is the more settled of the two. Written reviews complicate that: 69% of duoBooks's written reviews are positive against 100% of Readlang Mobile's, so the app with the better star average is not the one people write more warmly about.

duoBooks ships an update every 2 weeks, Readlang Mobile every 6 days. The most recent releases landed on September 21, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | duoBooks | Readlang Mobile |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (48 ratings)](https://appshunter.io/ios/app/duobooks-language-learning/id1538452253/reviews)** | [4.3 (3 ratings)](https://appshunter.io/ios/app/readlang-mobile/id6755721145/reviews) |
| Number of ratings | **48** | 3 |
| Positive reviews | 68.6% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | **Every 6 days** |
| Monetization | Free with in-app purchases | Freemium |
| Size | 54 MB | 35 MB |
| Requires iOS | **15.0** | 18.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 12+ | 17+ |
| Developer | [PlainProg LLC](https://appshunter.io/developer/1538452255) | [Alisher Fayzullaev](https://appshunter.io/developer/1855851596) |

## What reviewers say

### duoBooks

[App page](https://appshunter.io/ios/app/duobooks-language-learning/id1538452253)

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:** macOS Compatibility, Vision Pro support

**In-app purchases (11)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Plan | $2.99 | per month |
| Full Plan | $6.99 | per month |
| Full Plan | $17.99 | per year |
| 6 Month Full Plan | $19.99 | per 6 months |
| Full Yearly Plan | $29.99 | per year |
| War and Peace | $0.99 | one-time |
| Silver Blaze | $0.99 | one-time |
| On The River | $0.99 | one-time |
| Clochette | $0.99 | one-time |
| The Fishing Hole | $0.99 | one-time |
| Alice in Wonderland | $0.99 | one-time |


### Readlang Mobile

[App page](https://appshunter.io/ios/app/readlang-mobile/id6755721145)

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:** macOS Compatibility, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Readly Premium Monthly | $6.99 | per month |
| Readly Premium Yearly | $39.99 | per year |


## Frequently asked questions

### Is duoBooks free?

duoBooks is free to download, with in-app purchases available.

### Is Readlang Mobile free?

Readlang Mobile is free to download, with in-app purchases available.

### Which has better reviews, duoBooks or Readlang Mobile?

duoBooks is rated higher. duoBooks averages 4.7 out of 5 from 48 ratings, while Readlang Mobile averages 4.3 from 3 ratings.

### Do duoBooks or Readlang Mobile have ads?

Neither duoBooks nor Readlang Mobile shows ads.

### Which is updated more often, duoBooks or Readlang Mobile?

duoBooks ships an update every 2 weeks, and Readlang Mobile every 6 days. Most recently, duoBooks was updated on September 21, 2026 and Readlang Mobile on September 24, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*