# チャレンジ！ストップウォッチ vs Inner Clock Master

The clearest difference is ads: Inner Clock Master at none against チャレンジ！ストップウォッチ's shown. Inner Clock Master also leads on update cadence (every 4 days vs every 5 months). チャレンジ！ストップウォッチ's advantage is iOS requirement (11.0 vs 17.0). On price, 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.

チャレンジ！ストップウォッチ ships an update every 5 months, Inner Clock Master every 4 days. The most recent releases landed on October 27, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | チャレンジ！ストップウォッチ | Inner Clock Master |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 5 months | **Every 4 days** |
| Size | 44 MB | 19 MB |
| Requires iOS | **11.0** | 17.0 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Garhi Japan K.K.](https://appshunter.io/developer/1444709284) | [Ryoma Yanagimoto](https://appshunter.io/developer/1681944215) |

## What reviewers say

### チャレンジ！ストップウォッチ

[App page](https://appshunter.io/ios/app/id6443478369)

**In-app purchases:** none


### Inner Clock Master

[App page](https://appshunter.io/ios/app/inner-clock-master/id6757979617)

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

**In-app purchases:** none


## Frequently asked questions

### Is チャレンジ！ストップウォッチ free?

チャレンジ！ストップウォッチ is free to download, with no in-app purchases.

### Is Inner Clock Master free?

Inner Clock Master is free to download, with no in-app purchases.

### Do チャレンジ！ストップウォッチ or Inner Clock Master have ads?

チャレンジ！ストップウォッチ shows ads; Inner Clock Master does not.

### Which is updated more often, チャレンジ！ストップウォッチ or Inner Clock Master?

チャレンジ！ストップウォッチ ships an update every 5 months, and Inner Clock Master every 4 days. Most recently, チャレンジ！ストップウォッチ was updated on October 27, 2026 and Inner Clock Master on October 28, 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.*