# Gemetrix vs Rock Identifier | AI Scanner

The clearest difference is rating: Rock Identifier | AI Scanner at 4.3 against Gemetrix's 2.2. Rock Identifier | AI Scanner also leads on ratings volume (226 vs 5). Gemetrix's advantage is in-app purchases (none vs 3) and ads (none vs shown). On price and device support there is nothing between them.

Both are free to download. Rock Identifier | AI Scanner sells 3 in-app purchases, starting at $7.99 per 7 days. Gemetrix asks for nothing beyond the download.

Rock Identifier | AI Scanner holds the better App Store score, 4.3 against 2.2. That said, the two scores are not equally well evidenced: Rock Identifier | AI Scanner has 226 ratings behind it against 5, so its average is the more settled of the two. Written reviews complicate that: 50% of Gemetrix's written reviews are positive against 33% of Rock Identifier | AI Scanner's, so the app with the better star average is not the one people write more warmly about.

Gemetrix ships an update monthly, Rock Identifier | AI Scanner every 12 months. The most recent releases landed on October 24, 2026 and October 22, 2026 respectively.

## The numbers

| Metric | Gemetrix | Rock Identifier | AI Scanner |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.2 (5 ratings)](https://appshunter.io/ios/app/gemetrix/id1363103077/reviews) | **[4.3 (226 ratings)](https://appshunter.io/ios/app/rock-identifier-ai-scanner/id6444720183/reviews)** |
| Number of ratings | 5 | **226** |
| Positive reviews | **50.0% of reviews** | 33.3% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | **Monthly** | Every 12 months |
| Monetization | **Free** | Free with in-app purchases |
| Size | 18 MB | 154 MB |
| Requires iOS | **10.3** | 13.0 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [John Chapman](https://appshunter.io/developer/1363103076) | [MyApps](https://appshunter.io/developer/1654400413) |

## What reviewers say

### Gemetrix

[App page](https://appshunter.io/ios/app/gemetrix/id1363103077)

Control your smartphone camera's exposure, ISO, color temperature, and focus for both short-wave and long-wave UV illuminations. Compare captured images side-by-side or with a slider, and save them with clear labeling.

**Highlights:** UV illumination control (SWUV & LWUV), Adjustable exposure, ISO, color temperature, focus, Side-by-side image comparison, Image slider comparison, Save labeled images

**Features:** macOS Compatibility

**In-app purchases:** none


### Rock Identifier | AI Scanner

[App page](https://appshunter.io/ios/app/rock-identifier-ai-scanner/id6444720183)

Instantly identify rocks, crystals, gemstones, and minerals by simply taking a photo. Access detailed information about over 6,000 stones and build your personal collection. Explore the natural world with this user-friendly AI-powered tool.

**Highlights:** AI rock identification by photo, Identify rocks, minerals, crystals, gemstones, Accurate recognition via machine learning, Build personal rock collection, Access in-depth stone information, Offline identification mode

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Weekly | $7.99 | per 7 days |
| Stone Identifier Premium | $14.99 | per month |
| Stone Identifier Premium | $39.99 | per year |


## Frequently asked questions

### Is Gemetrix free?

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

### Is Rock Identifier | AI Scanner free?

Rock Identifier | AI Scanner is free to download, with in-app purchases available.

### Which has better reviews, Gemetrix or Rock Identifier | AI Scanner?

Rock Identifier | AI Scanner is rated higher. Gemetrix averages 2.2 out of 5 from 5 ratings, while Rock Identifier | AI Scanner averages 4.3 from 226 ratings.

### Do Gemetrix or Rock Identifier | AI Scanner have ads?

Rock Identifier | AI Scanner shows ads; Gemetrix does not.

### Which is updated more often, Gemetrix or Rock Identifier | AI Scanner?

Gemetrix ships an update monthly, and Rock Identifier | AI Scanner every 12 months. Most recently, Gemetrix was updated on October 24, 2026 and Rock Identifier | AI Scanner on October 22, 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.*