# 間違い問題メモ vs Abacus Practice

The clearest difference is price: 間違い問題メモ at Free against Abacus Practice's $0.99. 間違い問題メモ also leads on in-app purchases (none vs 1) and iOS requirement (15.5 vs 17.0). Abacus Practice's advantage is device support.

間違い問題メモ is free to download; Abacus Practice costs $0.99 up front. Abacus Practice sells 1 one-off in-app purchase. 間違い問題メモ asks for nothing beyond the download.

## The numbers

| Metric | 間違い問題メモ | Abacus Practice |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | — | No |
| Update frequency | — | Every 4 months |
| Monetization | — | Free with in-app purchases |
| Size | 5 MB | 18 MB |
| Requires iOS | **15.5** | 17.0 |
| Devices | — | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Risako Asai](https://appshunter.io/developer/1671273580) | [SMART BIT K.K](https://appshunter.io/developer/1896559487) |

## What reviewers say

### 間違い問題メモ

[App page](https://appshunter.io/ios/app/id1626302272)

**In-app purchases:** none


### Abacus Practice

[App page](https://appshunter.io/ios/app/abacus-practice-mental-math/id6770438521)

Practice abacus, mental arithmetic, and calculation skills on your iPhone or iPad. Features a realistic abacus interface for various exercises, including addition, subtraction, multiplication, division, and flash calculations. Track your progress and review your performance over time.

**Highlights:** Realistic abacus interface, Practice addition, subtraction, multiplication, division, Flash and slip calculations, Customizable problem generation, Practice history and performance records, Adjustable settings for sound, vibration, and left-handed mode

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Proアンロック | $2.99 | one-time |


## Frequently asked questions

### Is 間違い問題メモ free?

間違い問題メモ is free to download, with no in-app purchases.

### Is Abacus Practice free?

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

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*