# CO2 sensor vs Cacophony Sidekick

The clearest difference is update cadence: Cacophony Sidekick at every 2 months against CO2 sensor's every 18 months. 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 sensor ships an update every 18 months, Cacophony Sidekick every 2 months. The most recent releases landed on September 16, 2026 and June 8, 2026 respectively.

## The numbers

| Metric | CO2 sensor | Cacophony Sidekick |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[2.7 (3 ratings)](https://appshunter.io/ios/app/co2-sensor/id1643286074/reviews)** | — |
| Number of ratings | **3** | — |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 18 months | **Every 2 months** |
| Monetization | Free | Free |
| Size | 0 MB | 37 MB |
| Requires iOS | 15.6 | 15.6 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [sighmon](https://appshunter.io/developer/377815161) | [THE CACOPHONY PROJECT LIMITED](https://appshunter.io/developer/1664295665) |

## What reviewers say

### CO2 sensor

[App page](https://appshunter.io/ios/app/co2-sensor/id1643286074)

Monitor CO2, temperature, and humidity levels in real-time using a Bluetooth sensor. Save readings with location data and sync them across Apple devices via iCloud. View historical data on a map.

**Highlights:** Real-time CO2, temperature, and humidity readings, Bluetooth sensor integration, Save readings with location, iCloud sync across devices, Map view of saved readings, Open source code available

**In-app purchases:** none


### Cacophony Sidekick

[App page](https://appshunter.io/ios/app/cacophony-sidekick/id1664295663)

This application allows users to remotely monitor and protect wildlife by connecting to thermal and IR cameras in remote locations. It enables configuration of devices, playback of audio, and network connections. Users can view and tag captured videos on a website, receiving real-time data and alerts for conservation efforts.

**Highlights:** Remote camera connection, Wildlife monitoring, Device configuration, Real-time data and alerts, Video tagging, Open-source

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is CO2 sensor free?

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

### Is Cacophony Sidekick free?

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

### Do CO2 sensor or Cacophony Sidekick have ads?

Neither CO2 sensor nor Cacophony Sidekick shows ads.

### Which is updated more often, CO2 sensor or Cacophony Sidekick?

CO2 sensor ships an update every 18 months, and Cacophony Sidekick every 2 months. Most recently, CO2 sensor was updated on September 16, 2026 and Cacophony Sidekick on June 8, 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.*