# Millimeter Pro vs Calctan

The clearest difference is price: Calctan at Free against Millimeter Pro's $3.99. Millimeter Pro's advantage is in-app purchases (none vs 1) and ads (none vs shown). On rating, ratings volume, update cadence and device support there is nothing between them.

Calctan is free to download; Millimeter Pro costs $3.99 up front. Calctan sells 1 one-off in-app purchase. Millimeter Pro asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.4 for Millimeter Pro against 4.5 for Calctan. Both are backed by a comparable volume of ratings — 109 and 61 respectively. Written reviews are what separate them: 58% of Millimeter Pro's written reviews are positive against 29% of Calctan's.

Millimeter Pro ships an update every 4 months, Calctan every 3 months. Both last shipped on October 24, 2026.

## The numbers

| Metric | Millimeter Pro | Calctan |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | [4.4 (109 ratings)](https://appshunter.io/ios/app/millimeter-pro-screen-ruler/id631810777/reviews) | **[4.5 (61 ratings)](https://appshunter.io/ios/app/calctan/id1445480535/reviews)** |
| Number of ratings | **109** | 61 |
| Positive reviews | **57.9% of reviews** | 28.6% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 4 months | **Every 3 months** |
| Monetization | **Free** | Free with in-app purchases |
| Best chart rank | **#186** | — |
| Size | 24 MB | 11 MB |
| Requires iOS | **15.0** | 16.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [VisTech.Projects LLC](https://appshunter.io/developer/620969851) | [Jorge Lozada](https://appshunter.io/developer/421852863) |

## What reviewers say

### Millimeter Pro

[App page](https://appshunter.io/ios/app/millimeter-pro-screen-ruler/id631810777)

**Currently charting:** #186 Top Paid · Utilities (US App Store)

This app transforms your device into a versatile measuring tool. It allows for precise measurements of length, area, diameter, and angles using the touchscreen. Easily split objects into equal parts and switch between millimeters and inches for your convenience.

**Highlights:** Touchscreen ruler and tape measure, Measure length, area, diameter, and angles, Split objects into equal parts, Supports millimeters and inches, Estimate radius, Thread pitch gauge

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

**In-app purchases:** none


### Calctan

[App page](https://appshunter.io/ios/app/calctan/id1445480535)

This sophisticated calculator app offers a minimalist design with advanced mathematical functions and extensive personalization options. It seamlessly syncs across devices and includes multitasking features for enhanced productivity.

**Highlights:** Intuitive minimalist design, 100+ customizable themes, 47 advanced mathematical functions, Automatic calculation history, iCloud sync across devices, Split Screen and Swipe Mode multitasking, Share calculations easily

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| No Ads | $9.99 | one-time |


## Frequently asked questions

### Is Millimeter Pro free?

Millimeter Pro costs $3.99, with no in-app purchases.

### Is Calctan free?

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

### Which has better reviews, Millimeter Pro or Calctan?

Calctan is rated higher. Millimeter Pro averages 4.4 out of 5 from 109 ratings, while Calctan averages 4.5 from 61 ratings.

### Do Millimeter Pro or Calctan have ads?

Calctan shows ads; Millimeter Pro does not.

### Which is updated more often, Millimeter Pro or Calctan?

Millimeter Pro ships an update every 4 months, and Calctan every 3 months. Most recently, Millimeter Pro was updated on October 24, 2026 and Calctan 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.*