# iSeismometer vs Soil Explorer

The clearest difference is review sentiment: iSeismometer at 76% against Soil Explorer's 0%. iSeismometer also leads on ratings volume (172 vs 9). Soil Explorer's advantage is rating (4.1 vs 3.6) and iOS requirement (14.7 vs 16.0). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Soil Explorer holds the better App Store score, 4.1 against 3.6. That said, the two scores are not equally well evidenced: iSeismometer has 172 ratings behind it against 9, so its average is the more settled of the two. Written reviews complicate that: 76% of iSeismometer's written reviews are positive against 0% of Soil Explorer's, so the app with the better star average is not the one people write more warmly about.

iSeismometer ships an update every 7 months, Soil Explorer every 11 months. The most recent releases landed on October 22, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | iSeismometer | Soil Explorer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.6 (172 ratings)](https://appshunter.io/ios/app/iseismometer/id304190739/reviews) | **[4.1 (9 ratings)](https://appshunter.io/ios/app/soil-explorer/id996159565/reviews)** |
| Number of ratings | **172** | 9 |
| Positive reviews | **76.5% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 7 months** | Every 11 months |
| Monetization | Free | Free |
| Size | 3 MB | 172 MB |
| Requires iOS | 16.0 | **14.7** |
| Devices | iPhone, iPad, Mac | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [ObjectGraph LLC](https://appshunter.io/developer/284700705) | [Purdue University](https://appshunter.io/developer/371741257) |

## What reviewers say

### iSeismometer

[App page](https://appshunter.io/ios/app/iseismometer/id304190739)

Transform your iPhone into a sensitive seismometer to detect and visualize vibrations. Explore its educational and data-collecting capabilities for fun or serious applications.

**Highlights:** Converts iPhone to seismometer, Detects and visualizes vibrations, Data collecting capabilities, Educational use, Adjustable frequency settings, Re-track previous data, X-Y-Z illustrated graphs

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 🚀 Sensitive and accurate
- 👍 Simple and easy to use
- 💡 Useful for various applications (e.g. monitoring vibrations, detecting heartbeat)

**What reviewers complain about**

- 🐛 Crashes or freezes on newer devices
- 🔋 High battery consumption
- 🔒 Lacks security/privacy features (e.g. no option to disable data transmission)

**Reported bugs**

- Buttons/controls not working on newer iOS versions
- Keyboard not appearing in text input fields
- Inconsistent performance across device models

**Requested features**

- Add sensitivity control
- Implement zero control for reference plane
- Increase recording time
- Improve UI/UX (e.g. color coding, scrolling, chart speed control)
- Implement Richter scale or other measurement units


### Soil Explorer

[App page](https://appshunter.io/ios/app/soil-explorer/id996159565)

Discover detailed soil property and landscape maps for U.S. states and global soil distributions. Understand how map features relate to real-world observations. This educational tool uses data from USDA and USGS to illustrate complex soil-landscape relationships.

**Highlights:** Detailed soil property maps, Landscape visualizations, Global soil distribution maps, Field observation correlation, USDA NRCS data integration, USGS data integration

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is iSeismometer free?

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

### Is Soil Explorer free?

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

### Which has better reviews, iSeismometer or Soil Explorer?

Soil Explorer is rated higher. iSeismometer averages 3.6 out of 5 from 172 ratings, while Soil Explorer averages 4.1 from 9 ratings.

### Do iSeismometer or Soil Explorer have ads?

Neither iSeismometer nor Soil Explorer shows ads.

### Which is updated more often, iSeismometer or Soil Explorer?

iSeismometer ships an update every 7 months, and Soil Explorer every 11 months. Most recently, iSeismometer was updated on October 22, 2026 and Soil Explorer on October 17, 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.*