# Light Spectrometer Wavelength vs Planini

The clearest difference is in-app purchases: Planini at none against Light Spectrometer Wavelength's 7. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Light Spectrometer Wavelength sells 4 in-app purchases, starting at $0.99 per month. Planini asks for nothing beyond the download.

Light Spectrometer Wavelength ships an update every 2 months, Planini monthly. The most recent releases landed on October 22, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | Light Spectrometer Wavelength | Planini |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.2 (95 ratings)](https://appshunter.io/ios/app/light-spectrometer-wavelength/id6450930820/reviews)** | — |
| Number of ratings | **95** | — |
| Positive reviews | 72.7% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 2 months | **Monthly** |
| Monetization | Free with in-app purchases | — |
| Size | 43 MB | 6 MB |
| Requires iOS | **15.0** | 16.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [Contechity AB](https://appshunter.io/developer/1649290454) | [Daniel Schaedler](https://appshunter.io/developer/1892640749) |

## What reviewers say

### 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 |


### Planini

[App page](https://appshunter.io/ios/app/planini/id6762043307)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Light Spectrometer Wavelength free?

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

### Is Planini free?

Planini is free to download, with no in-app purchases.

### Do Light Spectrometer Wavelength or Planini have ads?

Neither Light Spectrometer Wavelength nor Planini shows ads.

### Which is updated more often, Light Spectrometer Wavelength or Planini?

Light Spectrometer Wavelength ships an update every 2 months, and Planini monthly. Most recently, Light Spectrometer Wavelength was updated on October 22, 2026 and Planini on October 8, 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.*