# Ultra N Back vs Sumflash

Ultra N Back and Sumflash are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

Both are free to download. Ultra N Back sells 2 in-app purchases, starting at $0.99 per month and Sumflash sells 1 in-app purchase, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

Ultra N Back ships an update every 4 days, Sumflash every 5 days. The most recent releases landed on October 10, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Ultra N Back | Sumflash |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | **Every 4 days** | Every 5 days |
| Size | 57 MB | 14 MB |
| Requires iOS | **16.0** | 17.0 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Ayumu Kawahara](https://appshunter.io/developer/1835186601) | [Toru Fukui](https://appshunter.io/developer/1888097145) |

## What reviewers say

### Ultra N Back

[App page](https://appshunter.io/ios/app/ultra-n-back-brain-training/id6751448185)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Plan | $0.99 | per month |
| Unlimited Plan | $1.99 | per month |


### Sumflash

[App page](https://appshunter.io/ios/app/sumflash-mental-math-flash/id6816003975)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium (Monthly) | $1.99 | per month |


## Frequently asked questions

### Is Ultra N Back free?

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

### Is Sumflash free?

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

### Do Ultra N Back or Sumflash have ads?

Both Ultra N Back and Sumflash show ads.

### Which is updated more often, Ultra N Back or Sumflash?

Ultra N Back ships an update every 4 days, and Sumflash every 5 days. Most recently, Ultra N Back was updated on October 10, 2026 and Sumflash on October 24, 2026.

---

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