# duoBooks vs ContextCat

The clearest difference is ads: duoBooks at none against ContextCat's shown. ContextCat's advantage is update cadence (weekly vs every 2 weeks). On price, in-app purchases, device support and iOS requirement there is nothing between them.

Both are free to download. duoBooks sells 4 in-app purchases, starting at $8.99 per month and ContextCat sells 3 in-app purchases, starting at $7.99 per month. Whichever you choose, the download price is not the number that matters.

duoBooks ships an update every 2 weeks, ContextCat weekly. The most recent releases landed on November 11, 2026 and November 12, 2026 respectively.

## The numbers

| Metric | duoBooks | ContextCat |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (61 ratings)](https://appshunter.io/ios/app/duobooks-language-learning/id1538452253/reviews)** | — |
| Number of ratings | **61** | — |
| Positive reviews | 68.4% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 2 weeks | **Weekly** |
| Monetization | Free with in-app purchases | — |
| Size | 55 MB | 77 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 12+ | 4+ |
| Developer | [PlainProg LLC](https://appshunter.io/developer/1538452255) | [Caner Gulay](https://appshunter.io/developer/1554769164) |

## What reviewers say

### duoBooks

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

Learn languages by reading books with instant translations and word explanations. Build vocabulary with spaced repetition and listen to accurate pronunciation. Supports EPUB files and offers a library of stories.

**Highlights:** Instant translation of any book, Word and sentence breakdown, Personalized vocabulary dictionary, Spaced repetition for vocabulary, Audio pronunciation for words/sentences, EPUB reader with bilingual texts, Library of 3000+ books

**Features:** macOS Compatibility, Vision Pro support, iPhone Duo support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Plan | $8.99 | per month |
| Full Yearly Plan | $19.99 | per year |
| 6 Month Full Plan | $24.99 | per 6 months |
| Full Yearly Plan | $39.99 | per year |


### ContextCat

[App page](https://appshunter.io/ios/app/contextcat-learn-by-reading/id6737737343)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ContextCat Pro (Monthly) | $7.99 | per month |
| ContextCat Pro (6 Months) | $24.99 | per 6 months |
| ContextCat Pro (Yearly) | $49.99 | per year |


## Frequently asked questions

### Is duoBooks free?

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

### Is ContextCat free?

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

### Do duoBooks or ContextCat have ads?

ContextCat shows ads; duoBooks does not.

### Which is updated more often, duoBooks or ContextCat?

duoBooks ships an update every 2 weeks, and ContextCat weekly. Most recently, duoBooks was updated on November 11, 2026 and ContextCat on November 12, 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.*