# O vs 安災システム

The clearest difference is in-app purchases: O at none against 安災システム's 1. 安災システム's advantage is iOS requirement (13.0 vs 15.6). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. 安災システム sells 1 one-off in-app purchase. O asks for nothing beyond the download.

O ships an update every 3 weeks, 安災システム monthly. The most recent releases landed on October 26, 2026 and June 25, 2026 respectively.

## The numbers

| Metric | O | 安災システム |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 80.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Monthly |
| Size | 16 MB | 115 MB |
| Requires iOS | 15.6 | **13.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [O-TECH JAPAN](https://appshunter.io/developer/1219186631) | [HORIKEN SOLUTIONS, CO., LTD](https://appshunter.io/developer/1558783872) |

## What reviewers say

### O

[App page](https://appshunter.io/ios/app/o-techmobile/id1246072028)

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

**In-app purchases:** none


### 安災システム

[App page](https://appshunter.io/ios/app/id1558783870)

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 注文請書発行料金 | $0.49 | one-time |


## Frequently asked questions

### Is O free?

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

### Is 安災システム free?

安災システム is free to download, with in-app purchases available.

### Do O or 安災システム have ads?

Neither O nor 安災システム shows ads.

### Which is updated more often, O or 安災システム?

O ships an update every 3 weeks, and 安災システム monthly. Most recently, O was updated on October 26, 2026 and 安災システム on June 25, 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.*