# Slant Gauge vs Protractor Smart

The clearest difference is ads: Protractor Smart at none against Slant Gauge's shown. Slant Gauge's advantage is update cadence (every 3 months vs every 21 months) and review sentiment (62% vs 44%). On price, in-app purchases, monetization model and device support there is nothing between them.

Both are free to download. Slant Gauge sells 1 one-off in-app purchase and Protractor Smart sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Slant Gauge ships an update every 3 months, Protractor Smart every 21 months. The most recent releases landed on October 15, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Slant Gauge | Protractor Smart |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.6 (246 ratings)](https://appshunter.io/ios/app/protractor-smart/id1076530001/reviews)** |
| Number of ratings | — | **246** |
| Positive reviews | **62.0% of reviews** | 43.6% of reviews |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | **Every 3 months** | Every 21 months |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 22 MB | 11 MB |
| Requires iOS | 15.6 | **14.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Isamu Sakamoto](https://appshunter.io/developer/598583811) | [ExaMobile S.A.](https://appshunter.io/developer/506014841) |

## What reviewers say

### Slant Gauge

[App page](https://appshunter.io/ios/app/slant-gauge/id598583808)

Measure angles and slopes with a simple digital display that rotates for easy viewing. This tool speaks the angle aloud, aiding in adjustment work. Calibration can improve its accuracy.

**Highlights:** Simple angle and slope measurement, Spoken angle output, Digital display rotates for visibility, Calibration for improved accuracy, Useful for adjustment work

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 角度傾斜計 | $1.99 | one-time |


### Protractor Smart

[App page](https://appshunter.io/ios/app/protractor-smart/id1076530001)

This app acts as a smart instrument for measuring angles using your device's camera. It offers two free modes for measuring angles on screen or using a plumb bob for slopes, with an additional premium mode for polygon measurements.

**Highlights:** Camera-based angle measurement, Touch measure mode, Plumb bob measure for slopes, Polygon measurement (premium), Screenshot functionality

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| AdBlock - Remove ads | $1.99 | one-time |

**What reviewers like**

- 👍 Useful for measurements
- 👍 Accurate for its purpose
- 👍 Convenient and handy
- 👍 Good for specific tasks (e.g., knife sharpening, stereo mic angles)
- 👍 No excessive charges

**What reviewers complain about**

- 🐛 App freezes/loads indefinitely
- 🐛 Does not launch after updates
- 🐛 Stuck on loading screen
- 🐛 Inaccurate or unstable measurements
- 🐛 Camera quality issues

**Reported bugs**

- App loads indefinitely
- App does not launch after iOS updates
- Stuck on loading screen
- Photo upload not possible in premium version
- Upside-down protractor on iOS

**Requested features**

- Improve camera function (light, zoom)
- Add automatic hold function
- Increase digital readout size
- Add more skins/cosmetics
- Option to remove ads


## Frequently asked questions

### Is Slant Gauge free?

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

### Is Protractor Smart free?

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

### Do Slant Gauge or Protractor Smart have ads?

Slant Gauge shows ads; Protractor Smart does not.

### Which is updated more often, Slant Gauge or Protractor Smart?

Slant Gauge ships an update every 3 months, and Protractor Smart every 21 months. Most recently, Slant Gauge was updated on October 15, 2026 and Protractor Smart 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.*