# NBack 3D vs AI先生　第一種電気主任技術者試験

The clearest difference is iOS requirement: NBack 3D at 15.6 against AI先生　第一種電気主任技術者試験's 17.0. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. NBack 3D sells 1 one-off in-app purchase and AI先生　第一種電気主任技術者試験 sells 2 in-app purchases, starting at $5.99 per month. Whichever you choose, the download price is not the number that matters.

NBack 3D ships an update every 10 months, AI先生　第一種電気主任技術者試験 every 8 months. The most recent releases landed on October 3, 2026 and October 1, 2026 respectively.

## The numbers

| Metric | NBack 3D | AI先生　第一種電気主任技術者試験 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/nback-3d/id1407606652/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 10 months | **Every 8 months** |
| Monetization | Free with in-app purchases | — |
| Size | 5 MB | 8 MB |
| Requires iOS | **15.6** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Yasuyoshi Ota](https://appshunter.io/developer/1500357652) | [reiko hori](https://appshunter.io/developer/1777370692) |

## What reviewers say

### NBack 3D

[App page](https://appshunter.io/ios/app/nback-3d/id1407606652)

This app challenges your memory by requiring you to count 3D shapes of specific colors. As the 'N' value increases, the difficulty escalates, testing your ability to recall past stimuli in a sequence.

**Highlights:** N-Back memory challenge, 3D shape and color recognition, Increasing difficulty levels, Sequence memorization, Cognitive skill enhancement

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Extend to 20'Back & Remove Ads | $2.99 | one-time |


### AI先生　第一種電気主任技術者試験

[App page](https://appshunter.io/ios/app/ai/id6738368835)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PROプラン | $5.99 | per month |
| PREMIUMプラン | $29.99 | per month |


## Frequently asked questions

### Is NBack 3D free?

NBack 3D is free to download, with in-app purchases available.

### Is AI先生　第一種電気主任技術者試験 free?

AI先生　第一種電気主任技術者試験 is free to download, with in-app purchases available.

### Do NBack 3D or AI先生　第一種電気主任技術者試験 have ads?

Both NBack 3D and AI先生　第一種電気主任技術者試験 show ads.

### Which is updated more often, NBack 3D or AI先生　第一種電気主任技術者試験?

NBack 3D ships an update every 10 months, and AI先生　第一種電気主任技術者試験 every 8 months. Most recently, NBack 3D was updated on October 3, 2026 and AI先生　第一種電気主任技術者試験 on October 1, 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.*