# 素因数分解クイズ vs CharSpin

The clearest difference is in-app purchases: 素因数分解クイズ at none against CharSpin's 3. 素因数分解クイズ also leads on iOS requirement (16.6 vs 18.0). CharSpin's advantage is ads (none vs shown). On price, update cadence and device support there is nothing between them.

Both are free to download. CharSpin sells 3 one-off in-app purchases. 素因数分解クイズ asks for nothing beyond the download.

Both ship on a similar rhythm, roughly every 5 days. The most recent releases landed on October 28, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | 素因数分解クイズ | CharSpin |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 5 days | Every 5 days |
| Size | 26 MB | 50 MB |
| Requires iOS | **16.6** | 18.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [YUKI WATANABE](https://appshunter.io/developer/1724288537) | [Nan-Kuang Lee](https://appshunter.io/developer/6779264786) |

## What reviewers say

### 素因数分解クイズ

[App page](https://appshunter.io/ios/app/1/id6740989986)

**Features:** macOS Compatibility

**In-app purchases:** none


### CharSpin

[App page](https://appshunter.io/ios/app/charspin/id6820187703)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Launch Set | $0.99 | one-time |
| Valkyrie & Wolf | $0.99 | one-time |
| S1 Pass | $4.99 | one-time |


## Frequently asked questions

### Is 素因数分解クイズ free?

素因数分解クイズ is free to download, with no in-app purchases.

### Is CharSpin free?

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

### Do 素因数分解クイズ or CharSpin have ads?

素因数分解クイズ shows ads; CharSpin does not.

### Which is updated more often, 素因数分解クイズ or CharSpin?

素因数分解クイズ ships an update every 5 days, and CharSpin every 5 days. Most recently, 素因数分解クイズ was updated on October 28, 2026 and CharSpin on October 31, 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.*