# What Gas? vs WCO CLiKC!

The clearest difference is update cadence: WCO CLiKC! at every 10 months against What Gas?'s every 37 months. What Gas?'s advantage is iOS requirement (13.0 vs 15.6). On price, ads, in-app purchases and device support there is nothing between them.

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

What Gas? ships an update every 37 months, WCO CLiKC! every 10 months. The most recent releases landed on October 11, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | What Gas? | WCO CLiKC! |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/what-gas/id1230722190/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 37 months | **Every 10 months** |
| Monetization | Free | — |
| Size | 24 MB | 40 MB |
| Requires iOS | **13.0** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 17+ | 12+ |
| Developer | [UNEP](https://appshunter.io/developer/1106793919) | [UPLearning B.V.](https://appshunter.io/developer/843256660) |

## What reviewers say

### What Gas?

[App page](https://appshunter.io/ios/app/what-gas/id1230722190)

This tool helps identify refrigerant gases, including ozone-depleting substances and their alternatives. It provides detailed information on chemical properties, hazards, and regulatory status for customs officers and technicians.

**Highlights:** Refrigerant gas identification, Information on ODS and alternatives, Details on ODP and GWP values, Searchable database, Flammability and hazard information, Montreal Protocol compliance data, Available in French and Spanish

**Features:** macOS Compatibility

**In-app purchases:** none


### WCO CLiKC!

[App page](https://appshunter.io/ios/app/wco-clikc/id6446645921)

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

**In-app purchases:** none


## Frequently asked questions

### Is What Gas? free?

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

### Is WCO CLiKC! free?

WCO CLiKC! is free to download, with no in-app purchases.

### Do What Gas? or WCO CLiKC! have ads?

Neither What Gas? nor WCO CLiKC! shows ads.

### Which is updated more often, What Gas? or WCO CLiKC!?

What Gas? ships an update every 37 months, and WCO CLiKC! every 10 months. Most recently, What Gas? was updated on October 11, 2026 and WCO CLiKC! on October 25, 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.*