# CASTDICE英単語帳 vs CoTan

The clearest difference is price: CoTan at Free against CASTDICE英単語帳's $17.99. CoTan also leads on update cadence (every 3 days vs every 5 weeks). CASTDICE英単語帳's advantage is ads (none vs shown). On in-app purchases, device support and iOS requirement there is nothing between them.

CoTan is free to download; CASTDICE英単語帳 costs $17.99 up front. Neither carries in-app purchases, so what you see is what you pay.

CASTDICE英単語帳 ships an update every 5 weeks, CoTan every 3 days. The most recent releases landed on September 21, 2026 and September 26, 2026 respectively.

## The numbers

| Metric | CASTDICE英単語帳 | CoTan |
| --- | --- | --- |
| Price | $17.99 | **Free** |
| Positive reviews | 85.0% of reviews | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 5 weeks | **Every 3 days** |
| Monetization | Paid | — |
| Size | 116 MB | 28 MB |
| Requires iOS | **15.0** | 15.1 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [CAST DICE, K.K.](https://appshunter.io/developer/1651974899) | [Ryo Minebayashi](https://appshunter.io/developer/1854415357) |

## What reviewers say

### CASTDICE英単語帳

[App page](https://appshunter.io/ios/app/castdice/id1563850616)

This app analyzes recent university entrance exam past papers using AI to compile a vocabulary list. Users can create custom English vocabulary books based on specific universities, departments, and time periods.

**Highlights:** AI analysis of past exam papers, Customizable vocabulary lists, University and department selection, Time period filtering, Vocabulary book creation

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

**In-app purchases:** none


### CoTan

[App page](https://appshunter.io/ios/app/cotan/id6755531559)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is CASTDICE英単語帳 free?

CASTDICE英単語帳 costs $17.99, with no in-app purchases.

### Is CoTan free?

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

### Do CASTDICE英単語帳 or CoTan have ads?

CoTan shows ads; CASTDICE英単語帳 does not.

### Which is updated more often, CASTDICE英単語帳 or CoTan?

CASTDICE英単語帳 ships an update every 5 weeks, and CoTan every 3 days. Most recently, CASTDICE英単語帳 was updated on September 21, 2026 and CoTan on September 26, 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.*