# Gas Detection vs Smell Annotator

The clearest difference is rating: Gas Detection at 5.0 against Smell Annotator's 1.0. Gas Detection also leads on iOS requirement (12.0 vs 15.0). Smell Annotator's advantage is update cadence (monthly vs every 16 months). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Gas Detection holds the better App Store score, 5.0 against 1.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively.

Gas Detection ships an update every 16 months, Smell Annotator monthly. The most recent releases landed on October 10, 2026 and October 2, 2026 respectively.

## The numbers

| Metric | Gas Detection | Smell Annotator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/gas-detection/id509211421/reviews)** | [1.0 (1 ratings)](https://appshunter.io/ios/app/smell-annotator/id1607528175/reviews) |
| Number of ratings | **2** | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 16 months | **Monthly** |
| Monetization | Free | Free |
| Size | 79 MB | 53 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Draegerwerk AG & Co. KGaA](https://appshunter.io/developer/646307986) | [SmartNanotubes Technologies](https://appshunter.io/developer/1607528177) |

## What reviewers say

### Gas Detection

[App page](https://appshunter.io/ios/app/gas-detection/id509211421)

Explore gas and vapor measurement technology with this app. It details Dräger-Tube, Dräger Sensor, and Dräger Chip systems, offering comprehensive listings of tubes and chips with measurement parameters. Learn about portable monitors and access support resources like compatibility charts and how-to videos.

**Highlights:** Gas and vapor measurement technology overview, Dräger-Tube, Sensor, and Chip system details, Complete listing of Dräger-Tubes and chips, Introduction to portable monitors, Sensor compatibility chart, How-to videos and error code charts

**Features:** macOS Compatibility

**In-app purchases:** none


### Smell Annotator

[App page](https://appshunter.io/ios/app/smell-annotator/id1607528175)

This application enables machines to digitally sense and analyze smells using nanomaterial-based technology. It allows users to view, annotate, and recognize smell measurements in real-time, functioning as part of a developer kit.

**Highlights:** Smell recognition, Smell digitalization and annotation, Saving and loading measurements, Real-time measurement visualization, Offline data collection, Graph synchronization

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Gas Detection free?

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

### Is Smell Annotator free?

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

### Which has better reviews, Gas Detection or Smell Annotator?

Gas Detection is rated higher. Gas Detection averages 5.0 out of 5 from 2 ratings, while Smell Annotator averages 1.0 from 1 ratings.

### Do Gas Detection or Smell Annotator have ads?

Neither Gas Detection nor Smell Annotator shows ads.

### Which is updated more often, Gas Detection or Smell Annotator?

Gas Detection ships an update every 16 months, and Smell Annotator monthly. Most recently, Gas Detection was updated on October 10, 2026 and Smell Annotator on October 2, 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.*