# Boost.AI 英作文添削・共通テスト英語 vs 不定方程式ガチャ

The clearest difference is price: Boost.AI 英作文添削・共通テスト英語 at Free against 不定方程式ガチャ's $3.99. Boost.AI 英作文添削・共通テスト英語 also leads on update cadence (every 4 days vs every 9 days) and iOS requirement (13.0 vs 17.0). 不定方程式ガチャ's advantage is in-app purchases (none vs 3). On ads and device support there is nothing between them.

Boost.AI 英作文添削・共通テスト英語 is free to download; 不定方程式ガチャ costs $3.99 up front. Boost.AI 英作文添削・共通テスト英語 sells 3 in-app purchases, starting at $5.99 per month. 不定方程式ガチャ asks for nothing beyond the download.

Boost.AI 英作文添削・共通テスト英語 ships an update every 4 days, 不定方程式ガチャ every 9 days. Both last shipped on October 24, 2026.

## The numbers

| Metric | Boost.AI 英作文添削・共通テスト英語 | 不定方程式ガチャ |
| --- | --- | --- |
| Price | **Free** | $3.99 |
| Positive reviews | 90.5% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 4 days** | Every 9 days |
| Monetization | Freemium | — |
| Size | 143 MB | 11 MB |
| Requires iOS | **13.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [ATSUSHI KIMURA](https://appshunter.io/developer/1829870349) | [Akira Hiraoka](https://appshunter.io/developer/1668714727) |

## What reviewers say

### Boost.AI 英作文添削・共通テスト英語

[App page](https://appshunter.io/ios/app/boostai/id6749287559)

This AI-powered app offers instant English writing feedback, detailed explanations, and AI chat for deeper understanding. It supports various writing styles and learning goals, helping users improve their English proficiency anytime, anywhere.

**Highlights:** Instant AI essay correction, Detailed explanations for errors, Handwriting recognition for essays, AI chat for clarification, Learning history management, Diverse question formats, Flashcards and English news

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Boost Pro 月額プラン | $5.99 | per month |
| 3ヶ月 | $11.99 | per 3 months |
| Boost Pro 年額プラン | $39.99 | per year |


### 不定方程式ガチャ

[App page](https://appshunter.io/ios/app/id6757098537)

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

**In-app purchases:** none


## Frequently asked questions

### Is Boost.AI 英作文添削・共通テスト英語 free?

Boost.AI 英作文添削・共通テスト英語 is free to download, with in-app purchases available.

### Is 不定方程式ガチャ free?

不定方程式ガチャ costs $3.99, with no in-app purchases.

### Do Boost.AI 英作文添削・共通テスト英語 or 不定方程式ガチャ have ads?

Neither Boost.AI 英作文添削・共通テスト英語 nor 不定方程式ガチャ shows ads.

### Which is updated more often, Boost.AI 英作文添削・共通テスト英語 or 不定方程式ガチャ?

Boost.AI 英作文添削・共通テスト英語 ships an update every 4 days, and 不定方程式ガチャ every 9 days. Most recently, Boost.AI 英作文添削・共通テスト英語 was updated on October 24, 2026 and 不定方程式ガチャ on October 24, 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.*