# Ruler - CM, MM, Inches — CM, MM, In. Measure Anything.

> Phone-based tool for precise length, width, and diagonal measurements. (iPhone/iPad app by Noadit, Inc..)

- Source: https://appshunter.io/ios/app/ruler-cm-mm-inches/id1022857549 (this page in markdown: same URL + `.md`)
- Developer: [Noadit, Inc.](https://appshunter.io/developer/1516754355)
- Category: Utilities, Reference
- Price: Free with in-app purchases
- Rating: 3.50/5 from 79 App Store ratings · 60 written reviews indexed
- Age rating: 4+
- Requires: iOS 16.0 · 6 MB
- Languages: American English, Chinese (Simplified, China), Chinese (Traditional, Taiwan)
- Released: 2015-08-12
- Data updated: 2026-08-23
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/ruler-cm-mm-inches/id1022857549/reviews.md

## What is Ruler?

Ditch bulky tools! Measure lengths, widths, and diagonals precisely anywhere with just your phone.

*** Features ***

► Smart Multi-Mode Measure
    *  Switch units freely: cm/mm, inch/fractions, with dual-unit display for instant comparison.
    *  Flexible starting points: Measure from screen edges or device edges for diverse scenarios.
    *  Full-direction coverage: Horizontal, vertical, or diagonal measurements. Paired with the 2.54m ultra-long scroll ruler, no corner is beyond reach!

► Zero-error Guarantee
    *  Auto-calibration tech: Dynamically adjusts based on device model, ensuring ≤1% error rate.
    *  Screen lock: Freeze measurements instantly to prevent accidental touches or slips.

► Contact Us
    *  Email: ceo@noadit.com

## Key features

- Multi-mode measurement (CM, MM, Inches, Fractions)
- Flexible starting points
- Full-direction measurement (horizontal, vertical, diagonal)
- Auto-calibration for accuracy
- Screen lock for preserving readings
- Ad-free VIP option

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| VIP | $4.99 | per month |

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Sponsor | $4.99 | one-time |
| Sponsor | $19.99 | one-time |
| Sponsor | $99.99 | one-time |


## What do users think of Ruler?

Overall sentiment: negative

**Pros**

- 👍 Simple and easy to use
- 📏 Accurate measurements (for some)
- 💡 Useful for small objects
- ✨ Clean interface
- 🚀 Fluid performance
- 🛠️ Good basic functionality

**Cons**

- 😠 Excessive and intrusive ads
- 🚫 Ads block measurements
- 🔊 Loud and shocking ads
- 💸 No option to pay for ad-free (or purchase lost)
- 📉 Inaccurate inch measurements (decimal vs. fractional)
- ⚠️ Shady download practices
- ⚫ Black screen issue
- 👆 Finger obscures measurements
- 📱 Inaccurate on specific devices
- 👎 Lost paid features after update

**Commonly reported bugs**

- Ads pop up constantly, making app unusable
- Ads overlay the ruler/measurements
- App crashes constantly
- Black screen issue
- Inaccurate measurements (especially inches)
- Paid no-ad version no longer works
- Calibration issues on specific devices
- Numbers are upside down
- Doesn't work with 10.5" iPad

**Most requested features**

- Option to remove ads via one-time purchase
- Ability to calibrate the ruler
- Offset crosshairs to see numbers
- Fractional inch (1/8, 1/16) display option
- Option to hide ruler digits
- Support for larger screen sizes (e.g., 10.5" iPad)
- Ability to scroll and see more than screen size
- Automatic screen size detection
- Landscape orientation support
- Add more measurement tools (plumb bob, seismometer, etc.)
- Option to hide calculator and other unwanted features
- Add click on every 1/10 of an inch in setup

## Recent user reviews (10 of 60)

All indexed reviews: https://appshunter.io/ios/app/ruler-cm-mm-inches/id1022857549/reviews.md

### 2/5 — Too much ads

*2026-05-30, version 26*

This app is pretty basic — nothing special or groundbreaking — but it’s completely ruined by the excessive ads. You get bombarded with them from start. It feels way too greedy for what it offers.

### 1/5 — Too many ads

*2025-10-01, version 6.3*

Ads keep popping up, even can’t use it.

### 1/5 — Ads block the ruler lol

*2025-01-12, version 5.2*

They literally put ads over the measurements, like, it’s a ruler app that hides the ruler to advertise to you. Hilariously bad.

### 4/5 — Simple and easy

*2024-03-14*

This is a very simple, flexible, and easy to use ruler app.  No frills, just ruler.  I like that you can have just cm or just inches or you can have both.  Only thing I’d change is that when they have both it doesn’t line up at zero.  Otherwise it would be 5 stars.  Under the settings there’s a way to remove the ads in kid mode.

### 1/5 — Beautiful simple app, Screaming loud ads

*2023-10-26, version 1.23.6*

Second time I opened the app I received an ad at the very top volume that my I pad could play. Nearly dropped it out of shock. No way to pay for a version without ads. It's a shame, as it is really nice. Deleting after 20 min.

### 4/5 — Ay man it’s pretty cool

*2023-09-24*

Cool ruler, I had to measure something that we all know what it is.

### 2/5 — No line from the start

*2023-09-04*

No line from the start

### 5/5 — Simply Perfect

*2023-08-18*

A thought experiment led me to search for this app. And sure enough, some genius had already developed it. In my opinion, every iPhone and iPad needs this. Mostly because I value quantification.

### 1/5 — Can’t see measurements under finger

*2023-08-16*

You can’t see the measurements under your finger as you adjust them. They should be slightly offset or fixed somewhere else

### 1/5 — inaccurate

*2023-07-15, version 1.23.6*

inaccurate by a lot.
1 1/4 pvc is measuring 1 3/4” in the app

## Frequently asked questions about Ruler

### What can this app measure?

This app allows you to measure lengths, widths, and diagonals of objects or spaces directly using your phone's screen. It supports various units, including centimeters, millimeters, inches, and fractions of inches, making it versatile for different needs.

### How accurate is the measurement?

The app features auto-calibration technology that dynamically adjusts based on your device model to ensure a low error rate, typically ≤1%. You can also use the screen lock feature to freeze measurements and prevent accidental slips or touches, further enhancing precision.

### Is this app free to use?

The app is free to download and use, offering core measurement functionalities. However, it also provides an optional VIP subscription for an ad-free experience, which is auto-renewable and priced per month. Details on subscription costs are available within the app.

### What devices is this app compatible with?

This app is designed for mobile devices and is available for download, implying compatibility with smartphones and tablets. The auto-calibration feature specifically adjusts based on the device model to optimize accuracy.

### How can I switch between measurement units?

You can freely switch between metric units (cm/mm) and imperial units (inch/fractions) within the app. It also offers a dual-unit display option, allowing for instant comparison between different measurement systems.

## Version history (last 5 releases)

### 26.1 — 2026-08-22

New UI designed for iOS 26.

### 26 — 2025-10-03

New user interface designed for iOS 26.

### 6.3 — 2025-09-16

Strengthened our core security to better protect your privacy and data.

### 6.2 — 2025-09-12

Strengthened our core security to better protect your privacy and data.

### 6.1 — 2025-08-29

Fixed the lagging issue when switching ruler types.

## Apps similar to Ruler

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Tape Measure & Ruler Арр](https://appshunter.io/ios/app/tape-measure-and-ruler/id1453537222) | 4.2 (4,291) | Free | Utilities |
| [Measurement app for iPhone](https://appshunter.io/ios/app/measurement-app-for-iphone/id1586541589) | 4.8 (108) | Free | Utilities |
| [Flying Ruler: 3D Tape Measure](https://appshunter.io/ios/app/flying-ruler-3d-tape-measure/id667579844) | 4.1 (187) | $1.99 | Utilities |
| [AR Ruler Cam: Tape Measure](https://appshunter.io/ios/app/ar-ruler-cam-tape-measure/id848139616) | 3.8 (8) | Free | Utilities |
| [Tape Measure+ AR Digital Ruler](https://appshunter.io/ios/app/tape-measure-plus-ar-digital-ruler/id1667165565) | 4.4 (931) | Free | Utilities |
| [Measure Tools: AR Room Planner](https://appshunter.io/ios/app/measure-tools-ar-room-planner/id1299651802) | 4.5 (143) | Free | Utilities |

## More apps by Noadit, Inc.

- [Photo Info Viewer - View Exif](https://appshunter.io/ios/app/photo-info-viewer-view-exif/id1023272476)
- [Compass & Level - Find North](https://appshunter.io/ios/app/compass-and-level-find-north/id1518520634)
- [Unit Converter - 14-in-1](https://appshunter.io/ios/app/unit-converter-14-in-1/id1587655048)
- [Protractor - Measure Angles](https://appshunter.io/ios/app/protractor-measure-angles/id1601838509)
- [Web Capture ME](https://appshunter.io/ios/app/web-capture-me/id1602264656)

All apps by Noadit, Inc.: https://appshunter.io/developer/1516754355

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-23.*