# 19×19 暗算脳トレ vs Double Digits

The clearest difference is ads: Double Digits at none against 19×19 暗算脳トレ's shown. 19×19 暗算脳トレ's advantage is update cadence (every 9 days vs every 5 weeks) and iOS requirement (13.0 vs 15.1). On price, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

19×19 暗算脳トレ ships an update every 9 days, Double Digits every 5 weeks. The most recent releases landed on October 7, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | 19×19 暗算脳トレ | Double Digits |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | **Every 9 days** | Every 5 weeks |
| Size | 38 MB | 28 MB |
| Requires iOS | **13.0** | 15.1 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Atsushi Isai](https://appshunter.io/developer/1881655484) | [shota shimogama](https://appshunter.io/developer/6796290145) |

## What reviewers say

### 19×19 暗算脳トレ

[App page](https://appshunter.io/ios/app/1919/id6763848289)

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

**In-app purchases:** none


### Double Digits

[App page](https://appshunter.io/ios/app/double-digits-mental-math/id6796290143)

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

**In-app purchases:** none


## Frequently asked questions

### Is 19×19 暗算脳トレ free?

19×19 暗算脳トレ is free to download, with no in-app purchases.

### Is Double Digits free?

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

### Do 19×19 暗算脳トレ or Double Digits have ads?

19×19 暗算脳トレ shows ads; Double Digits does not.

### Which is updated more often, 19×19 暗算脳トレ or Double Digits?

19×19 暗算脳トレ ships an update every 9 days, and Double Digits every 5 weeks. Most recently, 19×19 暗算脳トレ was updated on October 7, 2026 and Double Digits on October 11, 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.*