# Simple Pendulum Calculator vs Light Spectrometer Wavelength

The clearest difference is price: Light Spectrometer Wavelength at Free against Simple Pendulum Calculator's $2.99. Light Spectrometer Wavelength also leads on update cadence (every 2 months vs every 31 months) and ratings volume (95 vs 1). Simple Pendulum Calculator's advantage is rating (5.0 vs 4.2) and in-app purchases (none vs 7). On ads and device support there is nothing between them.

Light Spectrometer Wavelength is free to download; Simple Pendulum Calculator costs $2.99 up front. Light Spectrometer Wavelength sells 4 in-app purchases, starting at $0.99 per month. Simple Pendulum Calculator asks for nothing beyond the download.

Simple Pendulum Calculator holds the better App Store score, 5.0 against 4.2. That said, the two scores are not equally well evidenced: Light Spectrometer Wavelength has 95 ratings behind it against 1, so its average is the more settled of the two.

Simple Pendulum Calculator ships an update every 31 months, Light Spectrometer Wavelength every 2 months. The most recent releases landed on September 29, 2026 and October 22, 2026 respectively.

## The numbers

| Metric | Simple Pendulum Calculator | Light Spectrometer Wavelength |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/simple-pendulum-calculator/id1397285555/reviews)** | [4.2 (95 ratings)](https://appshunter.io/ios/app/light-spectrometer-wavelength/id6450930820/reviews) |
| Number of ratings | 1 | **95** |
| Positive reviews | — | 72.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 31 months | **Every 2 months** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 1 MB | 43 MB |
| Requires iOS | **13** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Nitrio](https://appshunter.io/developer/321121189) | [Contechity AB](https://appshunter.io/developer/1649290454) |

## What reviewers say

### Simple Pendulum Calculator

[App page](https://appshunter.io/ios/app/simple-pendulum-calculator/id1397285555)

This physics calculator quickly computes pendulum period, frequency, maximum height, energy, and speed. It supports various units, offers instant calculations with copyable results, and includes formulas for reference. Designed for privacy and efficiency, it works seamlessly on iOS devices.

**Highlights:** Instant pendulum calculations, Copyable results, Included formulas, Supports various units, High precision (16 decimal places), Ad-free and private

**Features:** macOS Compatibility

**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 Simple Pendulum Calculator free?

Simple Pendulum Calculator costs $2.99, 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, Simple Pendulum Calculator or Light Spectrometer Wavelength?

Simple Pendulum Calculator is rated higher. Simple Pendulum Calculator averages 5.0 out of 5 from 1 ratings, while Light Spectrometer Wavelength averages 4.2 from 95 ratings.

### Do Simple Pendulum Calculator or Light Spectrometer Wavelength have ads?

Neither Simple Pendulum Calculator nor Light Spectrometer Wavelength shows ads.

### Which is updated more often, Simple Pendulum Calculator or Light Spectrometer Wavelength?

Simple Pendulum Calculator ships an update every 31 months, and Light Spectrometer Wavelength every 2 months. Most recently, Simple Pendulum Calculator was updated on September 29, 2026 and Light Spectrometer Wavelength on October 22, 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.*