# iAddThree vs Dual N

The clearest difference is review sentiment: iAddThree at 100% against Dual N's 51%. iAddThree also leads on rating (5.0 vs 4.6). Dual N's advantage is ratings volume (376 vs 1) and iOS requirement (15.0 vs 17.0). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. iAddThree sells 1 one-off in-app purchase and Dual N sells 2 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

iAddThree holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: Dual N has 376 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 100% of iAddThree's written reviews are positive against 51% of Dual N's.

iAddThree ships an update every 3 weeks, Dual N fortnightly. The most recent releases landed on October 14, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | iAddThree | Dual N |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/iaddthree/id1389962750/reviews)** | [4.6 (376 ratings)](https://appshunter.io/ios/app/dual-n-back-brain-training/id1578693948/reviews) |
| Number of ratings | 1 | **376** |
| Positive reviews | **100.0% of reviews** | 50.9% of reviews |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 3 weeks | **Fortnightly** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 30 MB | 199 MB |
| Requires iOS | 17.0 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Nikolai Nobadi](https://appshunter.io/developer/1330360753) | [GOKAKU SUPPLI, LIMITED LIABILITY CO.](https://appshunter.io/developer/1440310107) |

## What reviewers say

### iAddThree

[App page](https://appshunter.io/ios/app/iaddthree/id1389962750)

Engage your mind with a unique math game that challenges your focus and cognitive abilities. The objective is to add three to each number presented, with a special rule where numbers wrap around to zero instead of forming double digits. This simple yet effective exercise provides a mental workout.

**Highlights:** Cognitive training, Focus improvement, Unique math rules, Brain exercise, High score challenges

**Features:** Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $0.99 | one-time |


### Dual N

[App page](https://appshunter.io/ios/app/dual-n-back-brain-training/id1578693948)

This app is a brain game designed to improve working memory and cognitive skills through a challenging memory-training exercise. It offers customizable difficulty, goal setting, and global leaderboards to track progress. An ad-free experience is available via a subscription.

**Highlights:** Working memory training, Customizable difficulty (N-value, interval, session length), Goal setting and reminders, Global leaderboards, Multilingual support, Ad-free Pro version

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| NBack Monthly Subscription | $0.99 | per month |
| Lifetime Pass | $12.99 | one-time |


## Frequently asked questions

### Is iAddThree free?

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

### Is Dual N free?

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

### Which has better reviews, iAddThree or Dual N?

iAddThree is rated higher. iAddThree averages 5.0 out of 5 from 1 ratings, while Dual N averages 4.6 from 376 ratings.

### Do iAddThree or Dual N have ads?

Both iAddThree and Dual N show ads.

### Which is updated more often, iAddThree or Dual N?

iAddThree ships an update every 3 weeks, and Dual N fortnightly. Most recently, iAddThree was updated on October 14, 2026 and Dual N on October 27, 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.*