# Lambda vs logSPL

The clearest difference is update cadence: logSPL at every 4 months against Lambda's every 54 months. logSPL also leads on review sentiment (100% vs 80%) and price ($1.99 vs $2.99). On rating, ratings volume, ads and in-app purchases there is nothing between them.

Lambda costs $2.99 and logSPL $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 5.0 for Lambda against 5.0 for logSPL. Both are backed by a comparable volume of ratings — 1 and 1 respectively. Written reviews are what separate them: 80% of Lambda's written reviews are positive against 100% of logSPL's.

Lambda ships an update every 54 months, logSPL every 4 months. The most recent releases landed on October 4, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | Lambda | logSPL |
| --- | --- | --- |
| Price | $2.99 | **$1.99** |
| Rating | [5.0 (1 ratings)](https://appshunter.io/ios/app/lambda/id434581690/reviews) | [5.0 (1 ratings)](https://appshunter.io/ios/app/logspl/id491999427/reviews) |
| Number of ratings | 1 | 1 |
| Positive reviews | 80.0% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 54 months | **Every 4 months** |
| Monetization | Paid | Paid |
| Size | 6 MB | 1 MB |
| Requires iOS | 15.6 | **15.2** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [dgApps](https://appshunter.io/developer/357488432) | [Fabien Lefebvre](https://appshunter.io/developer/338004167) |

## What reviewers say

### Lambda

[App page](https://appshunter.io/ios/app/lambda/id434581690)

This app helps musicians and sound engineers convert between musical notes, frequencies, and wavelengths. It features a dynamic fader, built-in oscillator, and frequency tracker with waveform display. Customize tuning standards and speed of sound for precise audio analysis.

**Highlights:** Convert notes, frequencies, wavelengths, Dynamic fader for real-time adjustment, Built-in oscillator with waveform, Frequency tracker with waveform, Customizable tuning standards, Adjustable speed of sound, Share data via standard methods

**In-app purchases:** none


### logSPL

[App page](https://appshunter.io/ios/app/logspl/id491999427)

This app functions as a sophisticated sound level meter, offering both basic and advanced features for measuring noise. It allows users to adjust update rates, select weighting types, and view historical data and real-time histograms. Calibration is recommended for optimal accuracy.

**Highlights:** Sound level measurement, Adjustable update rates (fast/slow), Weighting options (A, C, Z), Min/max value monitoring, Average value computation (Leq), Historical curve with grid, Real-time histogram, Dosemetering capabilities

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Lambda free?

Lambda costs $2.99, with no in-app purchases.

### Is logSPL free?

logSPL costs $1.99, with no in-app purchases.

### Which has better reviews, Lambda or logSPL?

Lambda and logSPL are both rated 5.0 out of 5 on the App Store, from 1 and 1 ratings respectively.

### Do Lambda or logSPL have ads?

Neither Lambda nor logSPL shows ads.

### Which is updated more often, Lambda or logSPL?

Lambda ships an update every 54 months, and logSPL every 4 months. Most recently, Lambda was updated on October 4, 2026 and logSPL 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.*