# StroopEffect2 vs ぱっとフラッシュ！

The clearest difference is price: ぱっとフラッシュ！ at Free against StroopEffect2's $2.99. ぱっとフラッシュ！ also leads on update cadence (every 3 weeks vs every 14 months) and iOS requirement (12.0 vs 15.6). StroopEffect2's advantage is in-app purchases (none vs 1). On ads and device support there is nothing between them.

ぱっとフラッシュ！ is free to download; StroopEffect2 costs $2.99 up front. ぱっとフラッシュ！ sells 1 one-off in-app purchase. StroopEffect2 asks for nothing beyond the download.

StroopEffect2 ships an update every 14 months, ぱっとフラッシュ！ every 3 weeks. The most recent releases landed on September 18, 2026 and September 26, 2026 respectively.

## The numbers

| Metric | StroopEffect2 | ぱっとフラッシュ！ |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 14 months | **Every 3 weeks** |
| Monetization | Paid | — |
| Size | 2 MB | 30 MB |
| Requires iOS | 15.6 | **12.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Yasuyoshi Ota](https://appshunter.io/developer/1500357652) | [takeshi hirayama](https://appshunter.io/developer/1806536875) |

## What reviewers say

### StroopEffect2

[App page](https://appshunter.io/ios/app/stroopeffect2/id1050388935)

This app demonstrates the psychological phenomenon known as the Stroop effect. It presents a time-trial game where users must identify the color of words, even when the word itself names a different color. It's a fun way to explore cognitive processing and reaction times.

**Highlights:** Stroop effect demonstration, Time trial game mode, Cognitive processing experiment, Reaction time measurement, Educational psychology tool

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

**In-app purchases:** none


### ぱっとフラッシュ！

[App page](https://appshunter.io/ios/app/id6744205174)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock Limit | $0.99 | one-time |


## Frequently asked questions

### Is StroopEffect2 free?

StroopEffect2 costs $2.99, with no in-app purchases.

### Is ぱっとフラッシュ！ free?

ぱっとフラッシュ！ is free to download, with in-app purchases available.

### Do StroopEffect2 or ぱっとフラッシュ！ have ads?

Neither StroopEffect2 nor ぱっとフラッシュ！ shows ads.

### Which is updated more often, StroopEffect2 or ぱっとフラッシュ！?

StroopEffect2 ships an update every 14 months, and ぱっとフラッシュ！ every 3 weeks. Most recently, StroopEffect2 was updated on September 18, 2026 and ぱっとフラッシュ！ 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.*