# 英単語9000 vs CheckBoostAudio

The clearest difference is update cadence: CheckBoostAudio at every 3 days against 英単語9000's every 22 months. On price, ads, in-app purchases and device support there is nothing between them.

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

英単語9000 ships an update every 22 months, CheckBoostAudio every 3 days. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | 英単語9000 | CheckBoostAudio |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/9000/id1311568845/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 22 months | **Every 3 days** |
| Monetization | Free | — |
| Size | 29 MB | 32 MB |
| Requires iOS | **12.0** | 13.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Kenta Shimomura](https://appshunter.io/developer/1286473553) | [Masatomo Fukuda](https://appshunter.io/developer/1599921920) |

## What reviewers say

### 英単語9000

[App page](https://appshunter.io/ios/app/9000/id1311568845)

This app helps users efficiently memorize vocabulary by focusing on words they are likely to forget. It utilizes a spaced repetition system based on the forgetting curve to reinforce learning and improve retention.

**Highlights:** 9000 vocabulary words included, Focuses on weak words based on forgetting curve, Push notifications for difficult words, Memory strength assessment, Efficient learning with occasional study sessions

**Features:** macOS Compatibility

**In-app purchases:** none


### CheckBoostAudio

[App page](https://appshunter.io/ios/app/checkboostaudio/id6740433605)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is 英単語9000 free?

英単語9000 is free to download, with no in-app purchases.

### Is CheckBoostAudio free?

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

### Do 英単語9000 or CheckBoostAudio have ads?

Neither 英単語9000 nor CheckBoostAudio shows ads.

### Which is updated more often, 英単語9000 or CheckBoostAudio?

英単語9000 ships an update every 22 months, and CheckBoostAudio every 3 days. Most recently, 英単語9000 was updated on October 24, 2026 and CheckBoostAudio on October 25, 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.*