# ワイヤレスCO2モニター vs Kowairo Voice

The clearest difference is update cadence: Kowairo Voice at every 2 weeks against ワイヤレスCO2モニター's every 11 months. ワイヤレスCO2モニター's advantage is iOS requirement (8.0 vs 18.0). 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.

ワイヤレスCO2モニター ships an update every 11 months, Kowairo Voice every 2 weeks. The most recent releases landed on October 10, 2026 and October 16, 2026 respectively.

## The numbers

| Metric | ワイヤレスCO2モニター | Kowairo Voice |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 11 months | **Every 2 weeks** |
| Size | 4 MB | 35 MB |
| Requires iOS | **8.0** | 18.0 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Step One Limited](https://appshunter.io/developer/646296997) | [TAKAYOSHI YOSHIKAWA](https://appshunter.io/developer/1882343499) |

## What reviewers say

### ワイヤレスCO2モニター

[App page](https://appshunter.io/ios/app/co2/id1162038614)

**Features:** macOS Compatibility

**In-app purchases:** none


### Kowairo Voice

[App page](https://appshunter.io/ios/app/kowairo-voice/id6782555687)

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

**In-app purchases:** none


## Frequently asked questions

### Is ワイヤレスCO2モニター free?

ワイヤレスCO2モニター is free to download, with no in-app purchases.

### Is Kowairo Voice free?

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

### Do ワイヤレスCO2モニター or Kowairo Voice have ads?

Neither ワイヤレスCO2モニター nor Kowairo Voice shows ads.

### Which is updated more often, ワイヤレスCO2モニター or Kowairo Voice?

ワイヤレスCO2モニター ships an update every 11 months, and Kowairo Voice every 2 weeks. Most recently, ワイヤレスCO2モニター was updated on October 10, 2026 and Kowairo Voice on October 16, 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.*