# One By One vs Numbly

The clearest difference is in-app purchases: Numbly at none against One By One's 3. Numbly also leads on ads (none vs shown) and update cadence (every 4 days vs every 2 weeks). One By One's advantage is ratings volume (77 vs 6). On price, device support and iOS requirement there is nothing between them.

Both are free to download. One By One sells 3 in-app purchases, starting at $1.99 per month. Numbly asks for nothing beyond the download.

Numbly holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: One By One has 77 ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 91% of One By One's written reviews are positive against 100% of Numbly's.

One By One ships an update every 2 weeks, Numbly every 4 days. Both last shipped on October 24, 2026.

## The numbers

| Metric | One By One | Numbly |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.8 (77 ratings)](https://appshunter.io/ios/app/one-by-one-mental-math/id1555846023/reviews) | **[5.0 (6 ratings)](https://appshunter.io/ios/app/numbly/id6480306932/reviews)** |
| Number of ratings | **77** | 6 |
| Positive reviews | 90.9% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 2 weeks | **Every 4 days** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 64 MB | 37 MB |
| Requires iOS | **15.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Brice Brown](https://appshunter.io/developer/1555846025) | [John Cahill](https://appshunter.io/developer/1738656621) |

## What reviewers say

### One By One

[App page](https://appshunter.io/ios/app/one-by-one-mental-math/id1555846023)

Practice arithmetic, algebra, trigonometry, and calculus with a retro-style math game. Level up by solving problems, unlock new challenges, and compete on leaderboards. Enhance your skills with artifacts and strategic upgrades.

**Highlights:** Randomly generated math problems, Leveling system with unlockable content, Practice arithmetic, algebra, trigonometry, and calculus, Retro ASCII art and music style, Leaderboards and achievements, Math artifacts and upgrades, AI battle mode for targeted practice

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Support | $1.99 | per month |
| Yearly Support | $12.99 | per year |
| Lifetime Supporter pass | $19.99 | one-time |


### Numbly

[App page](https://appshunter.io/ios/app/numbly/id6480306932)

Engage in a daily numerical puzzle where you use six numbers and operators to reach a target sum. Enjoy unlimited gameplay in workout mode and share your achievements with friends. Access answers to help you progress through challenging math puzzles.

**Highlights:** Daily number challenges, Six numbers and operators, Target sum puzzles, Social sharing, Unlimited workout mode, Access to answers

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is One By One free?

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

### Is Numbly free?

Numbly is free to download, with no in-app purchases.

### Which has better reviews, One By One or Numbly?

Numbly is rated higher. One By One averages 4.8 out of 5 from 77 ratings, while Numbly averages 5.0 from 6 ratings.

### Do One By One or Numbly have ads?

One By One shows ads; Numbly does not.

### Which is updated more often, One By One or Numbly?

One By One ships an update every 2 weeks, and Numbly every 4 days. Most recently, One By One was updated on October 24, 2026 and Numbly on October 24, 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.*