# WaterQuality vs Underfoot

The clearest difference is price: Underfoot at Free against WaterQuality's $4.99. Underfoot also leads on update cadence (every 3 months vs every 5 months). WaterQuality's advantage is in-app purchases (none vs 2) and device support (3 vs 1). On ads there is nothing between them.

Underfoot is free to download; WaterQuality costs $4.99 up front. Underfoot sells 2 in-app purchases, starting at $2.99 per month. WaterQuality asks for nothing beyond the download.

WaterQuality ships an update every 5 months, Underfoot every 3 months. The most recent releases landed on October 9, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | WaterQuality | Underfoot |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/waterquality/id569193509/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 months** |
| Monetization | Paid | — |
| Size | 96 MB | 102 MB |
| Requires iOS | **11.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Stroud Water Research Center](https://appshunter.io/developer/1200990268) | [Jason Brannon](https://appshunter.io/developer/1868090060) |

## What reviewers say

### WaterQuality

[App page](https://appshunter.io/ios/app/waterquality/id569193509)

This educational app allows users of all ages to record stream study data and learn about water quality indicators. It functions offline and includes a field guide for identifying aquatic macroinvertebrates to assess pollution tolerance. Data can be exported for scientific research or educational purposes.

**Highlights:** Record stream study data, Learn about water quality indicators, Offline functionality, Macroinvertebrate field guide, Data export (print/email), Site location recording

**Features:** Vision Pro support

**In-app purchases:** none


### Underfoot

[App page](https://appshunter.io/ios/app/underfoot-bug-field-guide/id6786962032)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Underfoot Pro | $2.99 | per month |
| Underfoot Pro Annual | $24.99 | per year |


## Frequently asked questions

### Is WaterQuality free?

WaterQuality costs $4.99, with no in-app purchases.

### Is Underfoot free?

Underfoot is free to download, with in-app purchases available.

### Do WaterQuality or Underfoot have ads?

Neither WaterQuality nor Underfoot shows ads.

### Which is updated more often, WaterQuality or Underfoot?

WaterQuality ships an update every 5 months, and Underfoot every 3 months. Most recently, WaterQuality was updated on October 9, 2026 and Underfoot on October 6, 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.*