# CO2 Modeller vs CO2IN

The clearest difference is update cadence: CO2IN at every 2 months against CO2 Modeller's every 36 months. CO2 Modeller's advantage is iOS requirement (12.1 vs 15.0). 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.

CO2 Modeller ships an update every 36 months, CO2IN every 2 months. The most recent releases landed on October 2, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | CO2 Modeller | CO2IN |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[2.5 (2 ratings)](https://appshunter.io/ios/app/co2-modeller/id1037101261/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 75.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 36 months | **Every 2 months** |
| Monetization | Free | — |
| Size | 9 MB | 73 MB |
| Requires iOS | **12.1** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Alex Rogers](https://appshunter.io/developer/346832869) | [The CO2IN, a.s.](https://appshunter.io/developer/1580951797) |

## What reviewers say

### CO2 Modeller

[App page](https://appshunter.io/ios/app/co2-modeller/id1037101261)

Simulate the impact of reducing carbon emissions on climate change. This app generates projections for atmospheric CO2 concentration, global warming, sea level rise, and ocean acidification.

**Highlights:** Model carbon emission reductions, Simulate climate change effects, Project CO2 concentration, Estimate global warming, Predict sea level rise, Analyze ocean acidification

**Features:** macOS Compatibility

**In-app purchases:** none


### CO2IN

[App page](https://appshunter.io/ios/app/co2in/id1513533437)

**In-app purchases:** none


## Frequently asked questions

### Is CO2 Modeller free?

CO2 Modeller is free to download, with no in-app purchases.

### Is CO2IN free?

CO2IN is free to download, with no in-app purchases.

### Do CO2 Modeller or CO2IN have ads?

Neither CO2 Modeller nor CO2IN shows ads.

### Which is updated more often, CO2 Modeller or CO2IN?

CO2 Modeller ships an update every 36 months, and CO2IN every 2 months. Most recently, CO2 Modeller was updated on October 2, 2026 and CO2IN on October 10, 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.*