# Rockd vs MusselID

The clearest difference is rating: Rockd at 4.4 against MusselID's 3.0. Rockd also leads on update cadence (every 3 months vs every 19 months) and ratings volume (187 vs 3). MusselID's advantage is iOS requirement (12.0 vs 16.6). On price, ads, in-app purchases and monetization model there is nothing between them.

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

Rockd holds the better App Store score, 4.4 against 3.0. That said, the two scores are not equally well evidenced: Rockd has 187 ratings behind it against 3, so its average is the more settled of the two.

Rockd ships an update every 3 months, MusselID every 19 months. The most recent releases landed on November 6, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | Rockd | MusselID |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (187 ratings)](https://appshunter.io/ios/app/rockd/id1153056624/reviews)** | [3.0 (3 ratings)](https://appshunter.io/ios/app/musselid/id1478539883/reviews) |
| Number of ratings | **187** | 3 |
| Positive reviews | 73.6% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 19 months |
| Monetization | Free | Free |
| Size | 259 MB | 101 MB |
| Requires iOS | 16.6 | **12.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [University of Wisconsin-Madison Shared Apps](https://appshunter.io/developer/908478605) | [ScienceApps, L3C](https://appshunter.io/developer/1478539882) |

## What reviewers say

### Rockd

[App page](https://appshunter.io/ios/app/rockd/id1153056624)

Discover and document the geology around you. Access global geologic maps, 3D globes, and detailed summaries of your surroundings. Contribute your own observations and track your exploration of Earth's geologic history.

**Highlights:** Interactive global geologic maps, 3D virtual globe exploration, Field observation logging, Offline map caching, Paleogeographic map access, Stratigraphic column viewing, Geologic literature integration

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

**In-app purchases:** none

**What reviewers like**

- 🗺️ Comprehensive geological maps with detailed information
- 💡 Innovative integration of peer-reviewed references and literature
- 🧭 Built-in Brunton compass and clinometer tools
- 📱 User-friendly interface and intuitive navigation
- 🌍 Global coverage with paleomaps and stratigraphic data

**What reviewers complain about**

- 🐛 Black map display issues in offline and online modes
- 📍 GPS tracking and real-time position updates failing
- 🔌 Offline functionality severely limited or broken
- 🔐 Persistent login requirement without password saving
- ⚠️ Error dialogs that won't dismiss

**Reported bugs**

- Black map display in airplane mode and online
- Persistent error dialogs that cannot be dismissed
- GPS not tracking in real-time
- Offline check-ins not syncing properly
- Sign-up page jumps between fields and login page

**Requested features**

- Follow/friend mechanic to track other users' check-ins
- Rock identification tool from photo uploads
- Offline map download with customizable zoom levels
- Stereonet tool for structural geology
- Groundwater/aquifer information section


### MusselID

[App page](https://appshunter.io/ios/app/musselid/id1478539883)

Identify North American freshwater mussels using a character-based key. This educational tool presents probable results with images, aiding citizen scientists and ecologists in watershed research.

**Highlights:** North American freshwater mussel identification, Character-based key for reducing search space, Image-based probable result surfacing, Designed for citizen scientists and ecologists, Educational tool for watershed research

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Rockd free?

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

### Is MusselID free?

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

### Which has better reviews, Rockd or MusselID?

Rockd is rated higher. Rockd averages 4.4 out of 5 from 187 ratings, while MusselID averages 3.0 from 3 ratings.

### Do Rockd or MusselID have ads?

Neither Rockd nor MusselID shows ads.

### Which is updated more often, Rockd or MusselID?

Rockd ships an update every 3 months, and MusselID every 19 months. Most recently, Rockd was updated on November 6, 2026 and MusselID on November 3, 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.*