# Calcu vs Muster Army Builder

The clearest difference is in-app purchases: Calcu at none against Muster Army Builder's 1. Calcu also leads on iOS requirement (13.0 vs 18.0). Muster Army Builder's advantage is update cadence (every 3 days vs every 6 weeks). On price, ads and device support there is nothing between them.

Both are free to download. Muster Army Builder sells 1 one-off in-app purchase. Calcu asks for nothing beyond the download.

Calcu ships an update every 6 weeks, Muster Army Builder every 3 days. The most recent releases landed on October 7, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Calcu | Muster Army Builder |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (3 ratings)](https://appshunter.io/ios/app/calcu-gator/id6761209063/reviews)** | — |
| Number of ratings | **3** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Every 3 days** |
| Monetization | Free | — |
| Size | 16 MB | 6 MB |
| Requires iOS | **13.0** | 18.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Joe Watson](https://appshunter.io/developer/1888278003) | [JAMES ROBERT DE RUYTER](https://appshunter.io/developer/6786275348) |

## What reviewers say

### Calcu

[App page](https://appshunter.io/ios/app/calcu-gator/id6761209063)

This unofficial player aid assists with hit calculations for robot battle games. Easily input values, sum categories, and calculate hit probability based on dice rolls. Customize your experience with multiple color options.

**Highlights:** Input values for categories and robots, Sum all category values, Calculate hit probability, 2d6 dice roll simulation, Multiple color themes

**In-app purchases:** none


### Muster Army Builder

[App page](https://appshunter.io/ios/app/muster-army-builder/id6786288983)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Muster Pro | $4.99 | one-time |


## Frequently asked questions

### Is Calcu free?

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

### Is Muster Army Builder free?

Muster Army Builder is free to download, with in-app purchases available.

### Do Calcu or Muster Army Builder have ads?

Neither Calcu nor Muster Army Builder shows ads.

### Which is updated more often, Calcu or Muster Army Builder?

Calcu ships an update every 6 weeks, and Muster Army Builder every 3 days. Most recently, Calcu was updated on October 7, 2026 and Muster Army Builder on October 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.*