# Multisim Circuit Explorer vs CO2 Modeller

The clearest difference is review sentiment: CO2 Modeller at 75% against Multisim Circuit Explorer's 25%. CO2 Modeller also leads on rating (2.5 vs 2.3) and device support (3 vs 1). Multisim Circuit Explorer's advantage is update cadence (every 10 months vs every 36 months) and ratings volume (8 vs 2). On price, ads, in-app purchases and monetization model 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 holds the better App Store score, 2.5 against 2.3. Both are backed by a comparable volume of ratings — 8 and 2 respectively. Written reviews point the same way: 25% of Multisim Circuit Explorer's written reviews are positive against 75% of CO2 Modeller's.

Multisim Circuit Explorer ships an update every 10 months, CO2 Modeller every 36 months. The most recent releases landed on November 6, 2026 and November 2, 2026 respectively.

## The numbers

| Metric | Multisim Circuit Explorer | CO2 Modeller |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.3 (8 ratings)](https://appshunter.io/ios/app/multisim-circuit-explorer/id502586865/reviews) | **[2.5 (2 ratings)](https://appshunter.io/ios/app/co2-modeller/id1037101261/reviews)** |
| Number of ratings | **8** | 2 |
| Positive reviews | 25.0% of reviews | **75.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 10 months** | Every 36 months |
| Monetization | Free | Free |
| Size | 1 MB | 9 MB |
| Requires iOS | **4.2** | 12.1 |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [National Instruments](https://appshunter.io/developer/432100099) | [Alex Rogers](https://appshunter.io/developer/346832869) |

## What reviewers say

### Multisim Circuit Explorer

[App page](https://appshunter.io/ios/app/multisim-circuit-explorer/id502586865)

Explore and understand 18 common electronic circuits, including Ohm's law and operational amplifiers. This companion app allows immediate observation of parameter changes on circuit behavior. It's designed for students learning fundamental circuit theory.

**Highlights:** Explore 18 common electronic circuits, Observe immediate parameter effect, Learn Ohm's law, Understand voltage and current dividers, Study RC/RL filters and step response, Explore operational amplifiers

**Features:** macOS Compatibility

**In-app purchases:** none


### 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


## Frequently asked questions

### Is Multisim Circuit Explorer free?

Multisim Circuit Explorer is free to download, with no in-app purchases.

### Is CO2 Modeller free?

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

### Which has better reviews, Multisim Circuit Explorer or CO2 Modeller?

CO2 Modeller is rated higher. Multisim Circuit Explorer averages 2.3 out of 5 from 8 ratings, while CO2 Modeller averages 2.5 from 2 ratings.

### Do Multisim Circuit Explorer or CO2 Modeller have ads?

Neither Multisim Circuit Explorer nor CO2 Modeller shows ads.

### Which is updated more often, Multisim Circuit Explorer or CO2 Modeller?

Multisim Circuit Explorer ships an update every 10 months, and CO2 Modeller every 36 months. Most recently, Multisim Circuit Explorer was updated on November 6, 2026 and CO2 Modeller on November 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.*