# Challenge with Erin vs Juken

The clearest difference is review sentiment: Juken at 100% against Challenge with Erin's 63%. Juken also leads on update cadence (fortnightly vs every 5 months) and rating (5.0 vs 4.7). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Juken holds the better App Store score, 5.0 against 4.7. Both are backed by a comparable volume of ratings — 16 and 8 respectively. Written reviews point the same way: 63% of Challenge with Erin's written reviews are positive against 100% of Juken's.

Challenge with Erin ships an update every 5 months, Juken fortnightly. The most recent releases landed on October 20, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Challenge with Erin | Juken |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.7 (16 ratings)](https://appshunter.io/ios/app/challenge-with-erin/id1290748939/reviews) | **[5.0 (8 ratings)](https://appshunter.io/ios/app/juken/id1513428918/reviews)** |
| Number of ratings | **16** | 8 |
| Positive reviews | 62.5% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 months | **Fortnightly** |
| Monetization | Free | Free |
| Size | 290 MB | 86 MB |
| Requires iOS | 12.0 | **10.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [The Japan Foundation Japanese-Language Institute, Kansai](https://appshunter.io/developer/1023654861) | [OzBuilds, LLC](https://appshunter.io/developer/1513428917) |

## What reviewers say

### Challenge with Erin

[App page](https://appshunter.io/ios/app/challenge-with-erin/id1290748939)

This app offers interactive lessons and quizzes to help users learn Japanese vocabulary, grammar, and culture. It features engaging games, manga-based dialogues, and cultural trivia to make studying enjoyable and effective. Track your progress, earn certificates, and compete with others on leaderboards.

**Highlights:** Interactive vocabulary games, Manga-based dialogue practice, Japanese culture quizzes, Progress tracking and points system, Weekly tests with certificates, Mini dictionary with Romanization

**Features:** Vision Pro support

**In-app purchases:** none


### Juken

[App page](https://appshunter.io/ios/app/juken/id1513428918)

This app offers a fast and efficient way to review WaniKani vocabulary. It uses a minimalistic interface with swipe gestures for quick answer submission, inspired by popular flashcard and dating apps. A WaniKani account is required to use its features.

**Highlights:** Minimalistic design, Fast review process, Swipe gestures for answers, Tinder-like interface, WaniKani integration

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

**In-app purchases:** none


## Frequently asked questions

### Is Challenge with Erin free?

Challenge with Erin is free to download, with no in-app purchases.

### Is Juken free?

Juken is free to download, with no in-app purchases.

### Which has better reviews, Challenge with Erin or Juken?

Juken is rated higher. Challenge with Erin averages 4.7 out of 5 from 16 ratings, while Juken averages 5.0 from 8 ratings.

### Do Challenge with Erin or Juken have ads?

Neither Challenge with Erin nor Juken shows ads.

### Which is updated more often, Challenge with Erin or Juken?

Challenge with Erin ships an update every 5 months, and Juken fortnightly. Most recently, Challenge with Erin was updated on October 20, 2026 and Juken on October 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.*