# 定規(Ruler) vs cm Ruler, device size measure

The clearest difference is rating: 定規(Ruler) at 5.0 against cm Ruler, device size measure's 1.0. 定規(Ruler) also leads on ads (none vs shown) and monetization model (free vs ad-supported). cm Ruler, device size measure's advantage is update cadence (every 5 days vs every 6 months). On price, ratings volume, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

定規(Ruler) holds the better App Store score, 5.0 against 1.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively.

定規(Ruler) ships an update every 6 months, cm Ruler, device size measure every 5 days. The most recent releases landed on October 24, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | 定規(Ruler) | cm Ruler, device size measure |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/ruler/id1166028258/reviews)** | [1.0 (1 ratings)](https://appshunter.io/ios/app/cm-ruler-device-size-measure/id6737493358/reviews) |
| Number of ratings | **2** | 1 |
| Positive reviews | 80.0% of reviews | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 6 months | **Every 5 days** |
| Monetization | **Free** | Ad-supported |
| Size | 3 MB | 23 MB |
| Requires iOS | **15.6** | 17.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Mayumi Kato](https://appshunter.io/developer/705832872) | [Taisuke Hosokawa](https://appshunter.io/developer/1585548762) |

## What reviewers say

### 定規(Ruler)

[App page](https://appshunter.io/ios/app/ruler/id1166028258)

A straightforward measuring tool for iPhones, offering accurate measurements in both millimeters and inches. It's designed for ease of use and provides a cool, functional experience for everyday measuring needs.

**Highlights:** Accurate measurements, Millimeter display, Inch display, Supports all iPhone sizes, Simple interface

**In-app purchases:** none


### cm Ruler, device size measure

[App page](https://appshunter.io/ios/app/cm-ruler-device-size-measure/id6737493358)

Transform your device into a versatile ruler for precise measurements. It displays width, height, and tapped positions, allowing you to record and share dimensions. Customize the ruler's appearance with different colors.

**Highlights:** Ruler UI for width and height, Measure tapped position size, Record and share measurements, Customizable ruler color

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

**In-app purchases:** none


## Frequently asked questions

### Is 定規(Ruler) free?

定規(Ruler) is free to download, with no in-app purchases.

### Is cm Ruler, device size measure free?

cm Ruler, device size measure is free to download, with no in-app purchases.

### Which has better reviews, 定規(Ruler) or cm Ruler, device size measure?

定規(Ruler) is rated higher. 定規(Ruler) averages 5.0 out of 5 from 2 ratings, while cm Ruler, device size measure averages 1.0 from 1 ratings.

### Do 定規(Ruler) or cm Ruler, device size measure have ads?

cm Ruler, device size measure shows ads; 定規(Ruler) does not.

### Which is updated more often, 定規(Ruler) or cm Ruler, device size measure?

定規(Ruler) ships an update every 6 months, and cm Ruler, device size measure every 5 days. Most recently, 定規(Ruler) was updated on October 24, 2026 and cm Ruler, device size measure on October 14, 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.*