# Mental Math Speed Trainer vs NBack³

The clearest difference is review sentiment: NBack³ at 71% against Mental Math Speed Trainer's 18%. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Mental Math Speed Trainer sells 3 in-app purchases, starting at $2.99 per month and NBack³ sells 1 in-app purchase, starting at $0.49 per month. Whichever you choose, the download price is not the number that matters.

Mental Math Speed Trainer ships an update weekly, NBack³ every 4 days. The most recent releases landed on September 22, 2026 and August 14, 2026 respectively.

## The numbers

| Metric | Mental Math Speed Trainer | NBack³ |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (4 ratings)](https://appshunter.io/ios/app/mental-math-speed-trainer/id6476421167/reviews)** | — |
| Number of ratings | **4** | — |
| Positive reviews | 17.6% of reviews | **71.4% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | Weekly | **Every 4 days** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 56 MB | 20 MB |
| Requires iOS | 17.2 | **17.0** |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [TAKAYUKI HASHIMOTO](https://appshunter.io/developer/1689527181) | [Taiki Nishimura](https://appshunter.io/developer/1780302048) |

## What reviewers say

### Mental Math Speed Trainer

[App page](https://appshunter.io/ios/app/mental-math-speed-trainer/id6476421167)

Sharpen your mental math skills with this engaging app focused on addition. Customize card numbers and timing intervals for a personalized learning experience. Track your progress with visually stimulating graphics, suitable for all ages.

**Highlights:** Customizable card numbers, Adjustable timing intervals, Focus on addition, Progress tracking, Engaging visuals, User-friendly interface

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 月間プラン | $2.99 | per month |
| 年間プラン | $19.99 | per year |
| Lifetime Premium | $39.99 | one-time |


### NBack³

[App page](https://appshunter.io/ios/app/nback-memory-training-game/id6745750227)

This brain training app uses the scientifically proven Dual N-Back method to enhance cognitive functions like working memory, focus, and decision-making. It offers adjustable difficulty levels and tracks progress with a visually engaging interface.

**Highlights:** Dual N-Back method, Adjustable difficulty (n=1-5), Enhances working memory, Improves inhibitory control, Develops attention skills, Progress tracking, Streak bonus system

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| プレミアムプラン | $0.49 | per month |


## Frequently asked questions

### Is Mental Math Speed Trainer free?

Mental Math Speed Trainer is free to download, with in-app purchases available.

### Is NBack³ free?

NBack³ is free to download, with in-app purchases available.

### Do Mental Math Speed Trainer or NBack³ have ads?

Both Mental Math Speed Trainer and NBack³ show ads.

### Which is updated more often, Mental Math Speed Trainer or NBack³?

Mental Math Speed Trainer ships an update weekly, and NBack³ every 4 days. Most recently, Mental Math Speed Trainer was updated on September 22, 2026 and NBack³ on August 14, 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.*