# Dark Sky Meter vs Light Spectrometer Wavelength

The clearest difference is price: Light Spectrometer Wavelength at Free against Dark Sky Meter's $1.99. Light Spectrometer Wavelength also leads on review sentiment (71% vs 40%) and rating (4.2 vs 3.8). Dark Sky Meter's advantage is in-app purchases (none vs 7). On update cadence, ads, device support and iOS requirement there is nothing between them.

Light Spectrometer Wavelength is free to download; Dark Sky Meter costs $1.99 up front. Light Spectrometer Wavelength sells 4 in-app purchases, starting at $0.99 per month. Dark Sky Meter asks for nothing beyond the download.

Light Spectrometer Wavelength holds the better App Store score, 4.2 against 3.8. That said, the two scores are not equally well evidenced: Light Spectrometer Wavelength has 96 ratings behind it against 6, so its average is the more settled of the two. Written reviews point the same way: 40% of Dark Sky Meter's written reviews are positive against 71% of Light Spectrometer Wavelength's.

Dark Sky Meter ships an update every 3 months, Light Spectrometer Wavelength every 2 months. The most recent releases landed on October 26, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | Dark Sky Meter | Light Spectrometer Wavelength |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | [3.8 (6 ratings)](https://appshunter.io/ios/app/dark-sky-meter/id602989060/reviews) | **[4.2 (96 ratings)](https://appshunter.io/ios/app/light-spectrometer-wavelength/id6450930820/reviews)** |
| Number of ratings | 6 | **96** |
| Positive reviews | 40.4% of reviews | **70.6% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 2 months** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 4 MB | 43 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [DDQ](https://appshunter.io/developer/418328467) | [Contechity AB](https://appshunter.io/developer/1649290454) |

## What reviewers say

### Dark Sky Meter

[App page](https://appshunter.io/ios/app/dark-sky-meter/id602989060)

This application utilizes your device's camera to measure the brightness of the night sky. The collected data can be optionally shared with scientific researchers worldwide.

**Highlights:** Measures sky brightness, Uses device camera, Optional data sharing, Contributes to scientific research

**Features:** Vision Pro support

**In-app purchases:** none


### Light Spectrometer Wavelength

[App page](https://appshunter.io/ios/app/light-spectrometer-wavelength/id6450930820)

This application analyzes light to determine its dominant wavelength in nanometers, frequency in terahertz, and period length in femtoseconds. It provides real-time measurements and allows users to save their findings with notes. The app is designed for measuring colored light sources.

**Highlights:** Measures dominant wavelength (nm), Measures frequency (THz), Measures period length (fs), Real-time measurement, Save measurements with notes, Optional calibration

**Features:** Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Access | $0.99 | per month |
| Full access | $0.99 | per month |
| Full access | $4.99 | per year |
| Full access | $6.99 | one-time |


## Frequently asked questions

### Is Dark Sky Meter free?

Dark Sky Meter costs $1.99, with no in-app purchases.

### Is Light Spectrometer Wavelength free?

Light Spectrometer Wavelength is free to download, with in-app purchases available.

### Which has better reviews, Dark Sky Meter or Light Spectrometer Wavelength?

Light Spectrometer Wavelength is rated higher. Dark Sky Meter averages 3.8 out of 5 from 6 ratings, while Light Spectrometer Wavelength averages 4.2 from 96 ratings.

### Do Dark Sky Meter or Light Spectrometer Wavelength have ads?

Neither Dark Sky Meter nor Light Spectrometer Wavelength shows ads.

### Which is updated more often, Dark Sky Meter or Light Spectrometer Wavelength?

Dark Sky Meter ships an update every 3 months, and Light Spectrometer Wavelength every 2 months. Most recently, Dark Sky Meter was updated on October 26, 2026 and Light Spectrometer Wavelength on October 27, 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.*