# Calcularium vs Duel

The clearest difference is in-app purchases: Duel at none against Calcularium's 7. Duel also leads on iOS requirement (13.0 vs 18.0). Calcularium's advantage is device support. On price there is nothing between them.

Both are free to download. Calcularium sells 7 in-app purchases, starting at $3.99 per month. Duel asks for nothing beyond the download.

## The numbers

| Metric | Calcularium | Duel |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (2.2K ratings)](https://appshunter.io/ios/app/calcularium/id824113384/reviews)** | — |
| Number of ratings | **2.2K** | — |
| Positive reviews | 67.3% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | — |
| Update frequency | Fortnightly | — |
| Monetization | Free with in-app purchases | — |
| Size | 52 MB | 93 MB |
| Requires iOS | 18.0 | **13.0** |
| Devices | **iPhone, iPad, Apple Watch** | — |
| Age rating | 4+ | 4+ |
| Developer | [InVooDoo LLC](https://appshunter.io/developer/1173246186) | [Maximilian Hemme](https://appshunter.io/developer/1657407562) |

## What reviewers say

### Calcularium

[App page](https://appshunter.io/ios/app/calcularium/id824113384)

This app offers real-time calculations, allowing you to see results as you type. It goes beyond basic arithmetic with advanced functions, unit conversions, and customizable expressions, acting as a powerful helper for complex calculations.

**Highlights:** Reactive Calculations, Voice Control (Siri), Script and Photo Input, Multi-Level Sub-Calculations, Editable History, Unit and Currency Conversion, Customizable Functions

**Features:** macOS Compatibility, Family Sharing, Apple Watch app, iMessage stickers, Vision Pro support

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Almighty Version | $3.99 | per month |
| Almighty Version | $4.99 | per 6 months |
| InVooDoo One | $5.99 | per month |
| Almighty Version | $29.99 | per year |
| Unlock Pro Version | $199.99 | one-time |
| Lifetime Almighty Version | $199.99 | one-time |
| Remove Ads Only | $199.99 | one-time |

**What reviewers like**

- 🚀 Powerful and feature-packed
- 👍 Easy to use with great tutorials
- 🎨 Beautiful and customizable design
- 💡 Innovative features like real-time calculation
- 🙌 Excellent value for money

**What reviewers complain about**

- 🔍 Confusing or unintuitive interface
- 📢 Excessive advertisements
- 🐛 Calculation errors or inconsistencies
- 🔒 Limited functionality in free version

**Reported bugs**

- Crashes or freezes on certain devices
- Incompatibility with older iOS versions
- Issues with calculator widget functionality

**Requested features**

- Add basic calculator functions like equal and clear buttons
- Improve unit conversion and scientific functions
- Integrate with Shortcuts and Siri
- Provide more customization options


### Duel

[App page](https://appshunter.io/ios/app/duel-desk/id1661032321)

**In-app purchases:** none


## Frequently asked questions

### Is Calcularium free?

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

### Is Duel free?

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

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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.*