# Thermal Light vs Hardness Unit Converter

The clearest difference is rating: Hardness Unit Converter at 4.0 against Thermal Light's 2.3. Hardness Unit Converter also leads on device support (3 vs 1). Thermal Light's advantage is review sentiment (50% vs 17%) and update cadence (weekly vs every 5 months). On price, ratings volume, ads and in-app purchases there is nothing between them.

Thermal Light costs $1.99 and Hardness Unit Converter $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Hardness Unit Converter holds the better App Store score, 4.0 against 2.3. Both are backed by a comparable volume of ratings — 6 and 7 respectively. Written reviews complicate that: 50% of Thermal Light's written reviews are positive against 17% of Hardness Unit Converter's, so the app with the better star average is not the one people write more warmly about.

Thermal Light ships an update weekly, Hardness Unit Converter every 5 months. The most recent releases landed on October 23, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Thermal Light | Hardness Unit Converter |
| --- | --- | --- |
| Price | $1.99 | $1.99 |
| Rating | [2.3 (6 ratings)](https://appshunter.io/ios/app/thermal-light/id476998738/reviews) | **[4.0 (7 ratings)](https://appshunter.io/ios/app/hardness-unit-converter/id1409248484/reviews)** |
| Number of ratings | 6 | **7** |
| Positive reviews | **50.0% of reviews** | 16.7% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Weekly** | Every 5 months |
| Monetization | Paid | Paid |
| Size | 2 MB | 1 MB |
| Requires iOS | 16.6 | **15.6** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Crystal Clear Solutions](https://appshunter.io/developer/444062170) | [Kei Suefuji](https://appshunter.io/developer/1388335881) |

## What reviewers say

### Thermal Light

[App page](https://appshunter.io/ios/app/thermal-light/id476998738)

This app measures the temperature of extremely hot objects by analyzing the light they emit. It's designed for users working with materials like iron, steel, and copper, offering a cost-effective alternative to specialized thermometers.

**Highlights:** Measures temperatures from 1000F to 2700F, Uses black body radiation analysis, Calibrated against certified IR thermometer, Cost-effective alternative to IR thermometers, Supports iron, steel, and ceramics

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

**In-app purchases:** none


### Hardness Unit Converter

[App page](https://appshunter.io/ios/app/hardness-unit-converter/id1409248484)

Easily convert hardness values between 12 different units, including Vickers, Brinell, Rockwell, and Shore. Input your value and select the desired unit for instant conversion, referencing ASTM E 140 standards and polynomial approximations for accuracy.

**Highlights:** Converts 12 hardness units, Vickers, Brinell, Rockwell, Shore support, Tensile strength conversion, ASTM E 140 reference, Polynomial approximation for data, Simple input and unit selection

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

**In-app purchases:** none


## Frequently asked questions

### Is Thermal Light free?

Thermal Light costs $1.99, with no in-app purchases.

### Is Hardness Unit Converter free?

Hardness Unit Converter costs $1.99, with no in-app purchases.

### Which has better reviews, Thermal Light or Hardness Unit Converter?

Hardness Unit Converter is rated higher. Thermal Light averages 2.3 out of 5 from 6 ratings, while Hardness Unit Converter averages 4.0 from 7 ratings.

### Do Thermal Light or Hardness Unit Converter have ads?

Neither Thermal Light nor Hardness Unit Converter shows ads.

### Which is updated more often, Thermal Light or Hardness Unit Converter?

Thermal Light ships an update weekly, and Hardness Unit Converter every 5 months. Most recently, Thermal Light was updated on October 23, 2026 and Hardness Unit Converter on October 25, 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.*