# 3n or Not vs 数学図鑑

The clearest difference is in-app purchases: 3n or Not at none against 数学図鑑's 2. 3n or Not also leads on device support (3 vs 1) and iOS requirement (14.0 vs 17.0). 数学図鑑's advantage is update cadence (every 2 weeks vs every 4 months). On price, review sentiment and ads there is nothing between them.

Both are free to download. 数学図鑑 sells 2 one-off in-app purchases. 3n or Not asks for nothing beyond the download.

3n or Not ships an update every 4 months, 数学図鑑 every 2 weeks. Both last shipped on October 8, 2026.

## The numbers

| Metric | 3n or Not | 数学図鑑 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (3 ratings)](https://appshunter.io/ios/app/3n-or-not/id913003589/reviews)** | — |
| Number of ratings | **3** | — |
| Positive reviews | 95.5% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 4 months | **Every 2 weeks** |
| Monetization | **Ad-supported** | Free with in-app purchases |
| Size | 13 MB | 149 MB |
| Requires iOS | **14.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Ninicode](https://appshunter.io/developer/647989501) | [Keisuke Minami](https://appshunter.io/developer/1719444621) |

## What reviewers say

### 3n or Not

[App page](https://appshunter.io/ios/app/3n-or-not/id913003589)

Test your quick thinking with this educational game.  It challenges you to rapidly identify if a given number is divisible by three. Perfect for practicing mental math skills.

**Highlights:** Quick number discrimination, Multiple of 3 identification, Mental math practice, Educational game

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

**In-app purchases:** none


### 数学図鑑

[App page](https://appshunter.io/ios/app/id6499109813)

This app uses animations and dynamic visuals to explain complex high school math concepts. It aims to make abstract ideas intuitive and engaging for students and educators alike. Explore calculus, geometry, and equations through visual learning.

**Highlights:** Animated explanations of math concepts, Dynamic visual representations, Covers calculus, geometry, and equations, Intuitive understanding of abstract ideas, Aids students and educators

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 広告の削除 | $1.99 | one-time |
| 広告の削除+開発者への支援 | $2.99 | one-time |


## Frequently asked questions

### Is 3n or Not free?

3n or Not is free to download, with no in-app purchases.

### Is 数学図鑑 free?

数学図鑑 is free to download, with in-app purchases available.

### Do 3n or Not or 数学図鑑 have ads?

Both 3n or Not and 数学図鑑 show ads.

### Which is updated more often, 3n or Not or 数学図鑑?

3n or Not ships an update every 4 months, and 数学図鑑 every 2 weeks. Most recently, 3n or Not was updated on October 8, 2026 and 数学図鑑 on October 8, 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.*