# One Arm vs Span

The clearest difference is in-app purchases: One Arm at none against Span's 1. One Arm also leads on iOS requirement (14.0 vs 17.0). Span's advantage is update cadence (every 6 days vs fortnightly). On price, ads and device support there is nothing between them.

Both are free to download. Span sells 1 one-off in-app purchase. One Arm asks for nothing beyond the download.

One Arm ships an update fortnightly, Span every 6 days. The most recent releases landed on November 9, 2026 and November 13, 2026 respectively.

## The numbers

| Metric | One Arm | Span |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Fortnightly | **Every 6 days** |
| Size | 63 MB | 60 MB |
| Requires iOS | **14.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 12+ | 4+ |
| Developer | [Eun Chan Kim](https://appshunter.io/developer/1719452740) | [Dodecki Labs](https://appshunter.io/developer/1571436485) |

## What reviewers say

### One Arm

[App page](https://appshunter.io/ios/app/one-arm/id6756837824)

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

**In-app purchases:** none


### Span

[App page](https://appshunter.io/ios/app/span-physics-bridge-builder/id6790187323)

**Features:** macOS Compatibility, Family Sharing, Vision Pro support, iPhone Duo support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Span Complete | $7.99 | one-time |


## Frequently asked questions

### Is One Arm free?

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

### Is Span free?

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

### Do One Arm or Span have ads?

Neither One Arm nor Span shows ads.

### Which is updated more often, One Arm or Span?

One Arm ships an update fortnightly, and Span every 6 days. Most recently, One Arm was updated on November 9, 2026 and Span on November 13, 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.*