# Onyomi vs OpenKoto

The clearest difference is price: OpenKoto at Free against Onyomi's $0.99. OpenKoto also leads on in-app purchases (none vs 1) and update cadence (weekly vs every 3 months). On ads, device support and iOS requirement there is nothing between them.

OpenKoto is free to download; Onyomi costs $0.99 up front. Onyomi sells 1 one-off in-app purchase. OpenKoto asks for nothing beyond the download.

Onyomi ships an update every 3 months, OpenKoto weekly. The most recent releases landed on October 13, 2026 and October 9, 2026 respectively.

## The numbers

| Metric | Onyomi | OpenKoto |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | **Weekly** |
| Size | 284 MB | 9 MB |
| Requires iOS | **17.0** | 18.0 |
| Devices | iPhone, iPad | **iPhone, iPad, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [玉杰 罗](https://appshunter.io/developer/1799696048) | [倍铭 刘](https://appshunter.io/developer/1831757727) |

## What reviewers say

### Onyomi

[App page](https://appshunter.io/ios/app/onyomi/id6748649854)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium | $0.99 | one-time |


### OpenKoto

[App page](https://appshunter.io/ios/app/openkoto/id6793335573)

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Onyomi free?

Onyomi costs $0.99, and also offers in-app purchases.

### Is OpenKoto free?

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

### Do Onyomi or OpenKoto have ads?

Neither Onyomi nor OpenKoto shows ads.

### Which is updated more often, Onyomi or OpenKoto?

Onyomi ships an update every 3 months, and OpenKoto weekly. Most recently, Onyomi was updated on October 13, 2026 and OpenKoto on October 9, 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.*