# 1級ボイラー技士 vs Jazz Theory

The clearest difference is in-app purchases: Jazz Theory at none against 1級ボイラー技士's 1. 1級ボイラー技士's advantage is update cadence (every 8 days vs every 2 weeks) and iOS requirement (16.0 vs 18.0). On price, ads and device support there is nothing between them.

Both are free to download. 1級ボイラー技士 sells 1 one-off in-app purchase. Jazz Theory asks for nothing beyond the download.

1級ボイラー技士 ships an update every 8 days, Jazz Theory every 2 weeks. The most recent releases landed on October 28, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | 1級ボイラー技士 | Jazz Theory |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 8 days** | Every 2 weeks |
| Size | 5 MB | 20 MB |
| Requires iOS | **16.0** | 18.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [TAKAYUKI OOTA](https://appshunter.io/developer/1855196437) | [ryusei kukita](https://appshunter.io/developer/1896759294) |

## What reviewers say

### 1級ボイラー技士

[App page](https://appshunter.io/ios/app/1/id6757117093)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1級ボイラー技士 試験対策 | $1.99 | one-time |


### Jazz Theory

[App page](https://appshunter.io/ios/app/jazz-theory/id6770638400)

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

**In-app purchases:** none


## Frequently asked questions

### Is 1級ボイラー技士 free?

1級ボイラー技士 is free to download, with in-app purchases available.

### Is Jazz Theory free?

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

### Do 1級ボイラー技士 or Jazz Theory have ads?

Neither 1級ボイラー技士 nor Jazz Theory shows ads.

### Which is updated more often, 1級ボイラー技士 or Jazz Theory?

1級ボイラー技士 ships an update every 8 days, and Jazz Theory every 2 weeks. Most recently, 1級ボイラー技士 was updated on October 28, 2026 and Jazz Theory 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.*