# ダイヤモンドZAi vs WhiteBook*

The clearest difference is ads: ダイヤモンドZAi at none against WhiteBook*'s shown. ダイヤモンドZAi also leads on iOS requirement (9.0 vs 15.0). WhiteBook*'s advantage is update cadence (monthly vs every 15 months). On price, in-app purchases and device support there is nothing between them.

Both are free to download. ダイヤモンドZAi sells 4 in-app purchases, starting at $7.49 per month and WhiteBook* sells 1 in-app purchase, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

ダイヤモンドZAi ships an update every 15 months, WhiteBook* monthly. The most recent releases landed on October 11, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | ダイヤモンドZAi | WhiteBook* |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 15 months | **Monthly** |
| Size | 31 MB | 41 MB |
| Requires iOS | **9.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [DIAMOND, Inc.](https://appshunter.io/developer/368890276) | [Tatsuya Fujisaka](https://appshunter.io/developer/1629171916) |

## What reviewers say

### ダイヤモンドZAi

[App page](https://appshunter.io/ios/app/zai/id527508296)

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ダイヤモンドZAi | $7.49 | per month |
| ダイヤモンドZAi | $21.49 | per 3 months |
| ダイヤモンドZAi | $37.99 | per 6 months |
| ダイヤモンドZAi | $76.99 | per year |


### WhiteBook*

[App page](https://appshunter.io/ios/app/whitebook/id1629171914)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| WhiteBook* plus | $3.99 | per month |


## Frequently asked questions

### Is ダイヤモンドZAi free?

ダイヤモンドZAi is free to download, with in-app purchases available.

### Is WhiteBook* free?

WhiteBook* is free to download, with in-app purchases available.

### Do ダイヤモンドZAi or WhiteBook* have ads?

WhiteBook* shows ads; ダイヤモンドZAi does not.

### Which is updated more often, ダイヤモンドZAi or WhiteBook*?

ダイヤモンドZAi ships an update every 15 months, and WhiteBook* monthly. Most recently, ダイヤモンドZAi was updated on October 11, 2026 and WhiteBook* on September 28, 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.*