# OneBook vs DejaVocab

The clearest difference is rating: OneBook at 5.0 against DejaVocab's 4.6. OneBook also leads on review sentiment (97% vs 87%) and iOS requirement (15.0 vs 17.6). On price, ratings volume, update cadence and ads there is nothing between them.

Both are free to download. OneBook sells 2 in-app purchases, starting at $8.00 per month and DejaVocab sells 6 in-app purchases, starting at $5.99 per month. Whichever you choose, the download price is not the number that matters.

OneBook holds the better App Store score, 5.0 against 4.6. Both are backed by a comparable volume of ratings — 64 and 64 respectively. Written reviews point the same way: 97% of OneBook's written reviews are positive against 87% of DejaVocab's.

Both ship on a similar rhythm, roughly weekly. Both last shipped on November 5, 2026.

## The numbers

| Metric | OneBook | DejaVocab |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (64 ratings)](https://appshunter.io/ios/app/onebook-language-learning/id6749743594/reviews)** | [4.6 (64 ratings)](https://appshunter.io/ios/app/dejavocab/id6753130604/reviews) |
| Number of ratings | 64 | 64 |
| Positive reviews | **97.3% of reviews** | 86.6% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Weekly | Weekly |
| Monetization | Freemium | Freemium |
| Size | 224 MB | 360 MB |
| Requires iOS | **15.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 17+ |
| Developer | [翊 林](https://appshunter.io/developer/1803147015) | [灏 龙](https://appshunter.io/developer/1842626848) |

## What reviewers say

### OneBook

[App page](https://appshunter.io/ios/app/onebook-language-learning/id6749743594)

This app offers a comprehensive language learning experience by integrating audiobooks, podcasts, and videos. It features AI-powered tools for instant text explanations, word lookup, and subtitle generation, supporting over 60 languages.

**Highlights:** AI Instant Tutor for text explanations, Automatic subtitle generation for audiobooks, Real-person narration for eBooks, Interactive PDF audio books, Efficient word and sentence lookup, Vocabulary level highlighting, Multiple reading modes

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| OneBook Premium Monthly | $8.00 | per month |
| AI Pack 1000 | $5.00 | one-time |


### DejaVocab

[App page](https://appshunter.io/ios/app/dejavocab/id6753130604)

This app helps you learn languages by immersing you in real-world content like videos, podcasts, and books. It builds a personal language corpus by capturing and organizing language chunks from natural input, allowing you to review words within their original context. The system integrates spoken and written language for a continuous learning experience.

**Highlights:** Learn from videos, podcasts, and audiobooks, Build a personal language corpus, Review vocabulary in original context, Integrates spoken and written language, Supports EPUB, PDF, and text files

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| DejaVocab 高级版 | $5.99 | per month |
| DejaVocab 高级版 | $7.99 | per month |
| DejaVocab 高级版年付 | $49.99 | per year |
| DejaVocab 专业版年付 | $69.99 | per year |
| DejaVocab 共建者 | $199.99 | one-time |
| DejaVocab 共建者 Plus | $299.99 | one-time |


## Frequently asked questions

### Is OneBook free?

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

### Is DejaVocab free?

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

### Which has better reviews, OneBook or DejaVocab?

OneBook is rated higher. OneBook averages 5.0 out of 5 from 64 ratings, while DejaVocab averages 4.6 from 64 ratings.

### Do OneBook or DejaVocab have ads?

Neither OneBook nor DejaVocab shows ads.

### Which is updated more often, OneBook or DejaVocab?

OneBook ships an update weekly, and DejaVocab weekly. Most recently, OneBook was updated on November 5, 2026 and DejaVocab on November 5, 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.*