# CO2 sensor vs Stud Finder Wall Wood Detector

The clearest difference is rating: Stud Finder Wall Wood Detector at 4.3 against CO2 sensor's 3.4. Stud Finder Wall Wood Detector also leads on update cadence (every 3 weeks vs every 12 months) and ratings volume (2.6K vs 7). CO2 sensor's advantage is in-app purchases (none vs 5) and iOS requirement (15.6 vs 17.0). On price, ads and device support there is nothing between them.

Both are free to download. Stud Finder Wall Wood Detector sells 5 in-app purchases, starting at $7.99 per 7 days. CO2 sensor asks for nothing beyond the download.

Stud Finder Wall Wood Detector holds the better App Store score, 4.3 against 3.4. That said, the two scores are not equally well evidenced: Stud Finder Wall Wood Detector has 2.6K 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 Wood Detector every 3 weeks. The most recent releases landed on October 24, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | CO2 sensor | Stud Finder Wall Wood Detector |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.4 (7 ratings)](https://appshunter.io/ios/app/co2-sensor/id1643286074/reviews) | **[4.3 (2.6K ratings)](https://appshunter.io/ios/app/stud-finder-wall-wood-detector/id6740814424/reviews)** |
| Number of ratings | 7 | **2.6K** |
| Positive reviews | — | 7.9% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 12 months | **Every 3 weeks** |
| Monetization | **Free** | Subscription |
| Size | 0 MB | 34 MB |
| Requires iOS | **15.6** | 17.0 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [sighmon](https://appshunter.io/developer/377815161) | [Appcellent](https://appshunter.io/developer/1870956141) |

## 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 Wood Detector

[App page](https://appshunter.io/ios/app/stud-finder-wall-wood-detector/id6740814424)

This app transforms your iOS device into a stud finder, helping you locate studs, nails, and metal objects behind walls. It offers precise detection with coordinate tracking and customizable alerts for safe and accurate installations.

**Highlights:** Intuitive indicator for easy value reading, Precise location detection with X, Y, Z coordinates, Vibration and audible notifications, Adjustable sensitivity settings, Apple Watch support for wrist scanning

**Features:** Apple Watch app

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Stud Finder Week | $7.99 | per 7 days |
| Stud Finder Weekly with Trial | $9.99 | per 7 days |
| Wall Wood Stud Finder Premium | $14.99 | per year |
| Stud Finder Annual with Trial | $29.99 | per year |
| Stud Finder Annual | $29.99 | per year |

**What reviewers like**

- 👍 Easy to use

**What reviewers complain about**

- 🐛 Doesn't work
- 🐛 No consistency
- 🐛 Can't detect wooden studs
- 💰 Waste of money
- 🤔 Unclear instructions

**Reported bugs**

- Doesn't work at all
- Indicates finding studs then doesn't
- Incompatible with walls where studs are visible

**Requested features**

- Dark mode option


## Frequently asked questions

### Is CO2 sensor free?

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

### Is Stud Finder Wall Wood Detector free?

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

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

Stud Finder Wall Wood Detector is rated higher. CO2 sensor averages 3.4 out of 5 from 7 ratings, while Stud Finder Wall Wood Detector averages 4.3 from 2.6K ratings.

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

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

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

CO2 sensor ships an update every 12 months, and Stud Finder Wall Wood Detector every 3 weeks. Most recently, CO2 sensor was updated on October 24, 2026 and Stud Finder Wall Wood Detector on October 31, 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.*