# Lambda Tuner vs GasUnits

The clearest difference is price: GasUnits at Free against Lambda Tuner's $3.99. GasUnits also leads on rating (5.0 vs 3.3) and update cadence (every 10 days vs every 19 months). Lambda Tuner's advantage is ratings volume (3 vs 1). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

GasUnits is free to download; Lambda Tuner costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

GasUnits holds the better App Store score, 5.0 against 3.3. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

Lambda Tuner ships an update every 19 months, GasUnits every 10 days. The most recent releases landed on September 21, 2026 and September 20, 2026 respectively.

## The numbers

| Metric | Lambda Tuner | GasUnits |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | [3.3 (3 ratings)](https://appshunter.io/ios/app/lambda-tuner/id632731065/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/gasunits/id6762513689/reviews)** |
| Number of ratings | **3** | 1 |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 19 months | **Every 10 days** |
| Monetization | Paid | **Free** |
| Size | 1 MB | 30 MB |
| Requires iOS | 16.6 | **15.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Johan Bjors](https://appshunter.io/developer/632731068) | [Vivek Chandra](https://appshunter.io/developer/461237208) |

## What reviewers say

### Lambda Tuner

[App page](https://appshunter.io/ios/app/lambda-tuner/id632731065)

This tool helps tune PID controllers using the Lambda method to calculate P, I, and D parameters. It's designed for intuitive use in various process industries and works on self-regulating and integrating loops. You can also use it to learn the impact of different PID parameters.

**Highlights:** Lambda method for PID parameter calculation, Supports self-regulating and integrating loops, Intuitive and easy to use interface, Adjustable Lambda value for reaction speed, Manual PID parameter testing, Educational tool for PID parameter impact

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

**In-app purchases:** none


### GasUnits

[App page](https://appshunter.io/ios/app/gasunits/id6762513689)

This app simplifies complex natural gas and LNG unit conversions for industry professionals. It accurately converts over 90 volume, rate, and price units, offering precise results and composition-based estimates. Easily copy formatted results for reports and models.

**Highlights:** Converts 90+ gas volume, rate, and price units, Supports three standard gas heating values, Calculates barrels of oil equivalent, Provides composition-based estimates, Fast, intuitive, and error-proof design, Copy results for reports and models

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

**In-app purchases:** none


## Frequently asked questions

### Is Lambda Tuner free?

Lambda Tuner costs $3.99, with no in-app purchases.

### Is GasUnits free?

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

### Which has better reviews, Lambda Tuner or GasUnits?

GasUnits is rated higher. Lambda Tuner averages 3.3 out of 5 from 3 ratings, while GasUnits averages 5.0 from 1 ratings.

### Do Lambda Tuner or GasUnits have ads?

Neither Lambda Tuner nor GasUnits shows ads.

### Which is updated more often, Lambda Tuner or GasUnits?

Lambda Tuner ships an update every 19 months, and GasUnits every 10 days. Most recently, Lambda Tuner was updated on September 21, 2026 and GasUnits on September 20, 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.*