# CO2 sensor vs Stud Finder Wall Detector Tool

The clearest difference is rating: Stud Finder Wall Detector Tool at 4.1 against CO2 sensor's 3.4. Stud Finder Wall Detector Tool also leads on update cadence (every 9 days vs every 12 months) and ratings volume (256 vs 7). CO2 sensor's advantage is in-app purchases (none vs 13). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Stud Finder Wall Detector Tool sells 12 in-app purchases, starting at $9.99 per 7 days. CO2 sensor asks for nothing beyond the download.

Stud Finder Wall Detector Tool holds the better App Store score, 4.1 against 3.4. That said, the two scores are not equally well evidenced: Stud Finder Wall Detector Tool has 256 ratings behind it against 7, so its average is the more settled of the two.

CO2 sensor ships an update every 12 months, Stud Finder Wall Detector Tool every 9 days. Both last shipped on October 24, 2026.

## The numbers

| Metric | CO2 sensor | Stud Finder Wall Detector Tool |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.4 (7 ratings)](https://appshunter.io/ios/app/co2-sensor/id1643286074/reviews) | **[4.1 (256 ratings)](https://appshunter.io/ios/app/stud-finder-wall-detector-tool/id6477968944/reviews)** |
| Number of ratings | 7 | **256** |
| Positive reviews | — | 6.1% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 12 months | **Every 9 days** |
| Monetization | **Free** | Subscription |
| Size | 0 MB | 19 MB |
| Requires iOS | **15.6** | 16.0 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [sighmon](https://appshunter.io/developer/377815161) | [Optimize IT](https://appshunter.io/developer/1671426874) |

## 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

**Features:** Vision Pro support

**In-app purchases:** none


### Stud Finder Wall Detector Tool

[App page](https://appshunter.io/ios/app/stud-finder-wall-detector-tool/id6477968944)

This multi-tool app helps you find studs, measure angles, and check levels with precision. It offers real-time visual, sound, and haptic alerts, along with an Apple Watch companion for convenient monitoring. Built-in tutorials guide you through its features.

**Highlights:** Magnetic stud finder with multiple presets, Accurate bubble level for surfaces, Advanced angle finder for measurements, Customizable sound and haptic feedback, Apple Watch companion app, Detailed visual indicators, Built-in tutorials and guides

**Features:** Apple Watch app

**In-app purchases (12)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly | $9.99 | per 7 days |
| Weekly Pro | $9.99 | per 7 days |
| Weekly VIP | $9.99 | per 7 days |
| Weekly | $12.99 | per 7 days |
| Monthly Pro | $17.99 | per month |
| Monthly | $19.99 | per month |
| Annual Pro | $29.99 | per year |
| Annual | $29.99 | per year |
| Annual VIP | $29.99 | per year |
| Annual VIP | $49.99 | per year |
| Monthly VIP | $49.99 | per month |
| Annual VIP | $99.99 | per year |

**What reviewers like**

- 👍 Worked great once
- 👍 Found the stud so fast
- 👍 Accurate stud finding

**What reviewers complain about**

- 👎 Does not work
- 👎 Scam app
- 👎 Waste of money
- 👎 Cannot cancel subscription
- 👎 Charged immediately

**Reported bugs**

- App falsely identifies studs when phone is in the air
- Scan never starts working
- Unable to cancel subscription
- Charged despite attempting to cancel
- App does not work

**Requested features**

- Improve accuracy on wood studs
- Provide clear instructions on how to use the app
- Offer a reliable cancellation method
- Add support for wood studs
- Fix the 'Start Scan' button issue


## Frequently asked questions

### Is CO2 sensor free?

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

### Is Stud Finder Wall Detector Tool free?

Stud Finder Wall Detector Tool is free to download, with in-app purchases available.

### Which has better reviews, CO2 sensor or Stud Finder Wall Detector Tool?

Stud Finder Wall Detector Tool is rated higher. CO2 sensor averages 3.4 out of 5 from 7 ratings, while Stud Finder Wall Detector Tool averages 4.1 from 256 ratings.

### Do CO2 sensor or Stud Finder Wall Detector Tool have ads?

Neither CO2 sensor nor Stud Finder Wall Detector Tool shows ads.

### Which is updated more often, CO2 sensor or Stud Finder Wall Detector Tool?

CO2 sensor ships an update every 12 months, and Stud Finder Wall Detector Tool every 9 days. Most recently, CO2 sensor was updated on October 24, 2026 and Stud Finder Wall Detector Tool on October 24, 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.*