# CO2 on Watch & Lockscreen vs BeepDetect

The clearest difference is in-app purchases: BeepDetect at none against CO2 on Watch & Lockscreen's 8. CO2 on Watch & Lockscreen's advantage is ads (none vs shown). On price, update cadence, device support and iOS requirement there is nothing between them.

Both are free to download. CO2 on Watch & Lockscreen sells 8 in-app purchases, starting at $1.99 per month. BeepDetect asks for nothing beyond the download.

CO2 on Watch & Lockscreen ships an update weekly, BeepDetect fortnightly. The most recent releases landed on June 4, 2026 and September 25, 2026 respectively.

## The numbers

| Metric | CO2 on Watch & Lockscreen | BeepDetect |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.0 (2 ratings)](https://appshunter.io/ios/app/co2-on-watch-and-lockscreen/id6738605498/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | **Weekly** | Fortnightly |
| Monetization | Free with in-app purchases | — |
| Size | 28 MB | 2 MB |
| Requires iOS | 17.6 | **17.0** |
| Devices | **iPhone, iPad, Apple Watch** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Kevin Floch](https://appshunter.io/developer/1772752224) | [Ruben Soto](https://appshunter.io/developer/1890251998) |

## What reviewers say

### CO2 on Watch & Lockscreen

[App page](https://appshunter.io/ios/app/co2-on-watch-and-lockscreen/id6738605498)

Monitor CO2 levels from compatible devices directly on your Apple Watch and iPhone Lock Screen. Receive smart alerts and view real-time air quality data with color-coded visuals for quick understanding.

**Highlights:** Apple Watch complications with history graph, iPhone Lock Screen widgets, Customizable CO2 threshold alerts, Background monitoring, Live Activity for real-time data, Color-coded air quality visuals

**Features:** macOS Compatibility

**In-app purchases (8)**

| Purchase | Price | Billing |
| --- | --- | --- |
| CO2_Monthly | $1.99 | per month |
| CO2_Annually | $9.99 | per year |
| Small tip | $4.99 | one-time |
| Medium tip | $9.99 | one-time |
| CO2_Lifetime_Upgrade2 | $14.99 | one-time |
| Large tip | $19.99 | one-time |
| CO2_Lifetime | $24.99 | one-time |
| Extra large tip | $49.99 | one-time |


### BeepDetect

[App page](https://appshunter.io/ios/app/beepdetect/id6761551923)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is CO2 on Watch & Lockscreen free?

CO2 on Watch & Lockscreen is free to download, with in-app purchases available.

### Is BeepDetect free?

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

### Do CO2 on Watch & Lockscreen or BeepDetect have ads?

BeepDetect shows ads; CO2 on Watch & Lockscreen does not.

### Which is updated more often, CO2 on Watch & Lockscreen or BeepDetect?

CO2 on Watch & Lockscreen ships an update weekly, and BeepDetect fortnightly. Most recently, CO2 on Watch & Lockscreen was updated on June 4, 2026 and BeepDetect on September 25, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*