# RedCrab Calculator vs Duodecuple Calc

The clearest difference is in-app purchases: Duodecuple Calc at none against RedCrab Calculator's 1. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. RedCrab Calculator sells 1 one-off in-app purchase. Duodecuple Calc asks for nothing beyond the download.

RedCrab Calculator ships an update fortnightly, Duodecuple Calc every 2 weeks. The most recent releases landed on August 30, 2026 and August 3, 2026 respectively.

## The numbers

| Metric | RedCrab Calculator | Duodecuple Calc |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | Yes | Yes |
| Update frequency | Fortnightly | **Every 2 weeks** |
| Size | 4 MB | 36 MB |
| Requires iOS | **15.6** | 15.8.3 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [少泽 梁](https://appshunter.io/developer/897112791) | [Hideaki Uchikoshi](https://appshunter.io/developer/1559575002) |

## What reviewers say

### RedCrab Calculator

[App page](https://appshunter.io/ios/app/redcrab-calculator/id947845140)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 终身会员 | $1.99 | one-time |


### Duodecuple Calc

[App page](https://appshunter.io/ios/app/duodecuple-calc/id6742208421)

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

**In-app purchases:** none


## Frequently asked questions

### Is RedCrab Calculator free?

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

### Is Duodecuple Calc free?

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

### Do RedCrab Calculator or Duodecuple Calc have ads?

Both RedCrab Calculator and Duodecuple Calc show ads.

### Which is updated more often, RedCrab Calculator or Duodecuple Calc?

RedCrab Calculator ships an update fortnightly, and Duodecuple Calc every 2 weeks. Most recently, RedCrab Calculator was updated on August 30, 2026 and Duodecuple Calc on August 3, 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.*