# Rock Identifier vs Space Arc

The clearest difference is in-app purchases: Space Arc at none against Rock Identifier's 3. Space Arc also leads on update cadence (monthly vs every 5 months) and rating (5.0 vs 4.8). Rock Identifier's advantage is ads (none vs shown). On price, ratings volume, device support and iOS requirement there is nothing between them.

Both are free to download. Rock Identifier sells 3 in-app purchases, starting at $2.99 per 7 days. Space Arc asks for nothing beyond the download.

Space Arc holds the better App Store score, 5.0 against 4.8. Both are backed by a comparable volume of ratings — 4 and 3 respectively.

Rock Identifier ships an update every 5 months, Space Arc monthly. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Rock Identifier | Space Arc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.8 (4 ratings)](https://appshunter.io/ios/app/rock-identifier-stone-id/id6755675894/reviews) | **[5.0 (3 ratings)](https://appshunter.io/ios/app/space-arc/id6759466047/reviews)** |
| Number of ratings | **4** | 3 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | Every 5 months | **Monthly** |
| Monetization | Freemium | **Ad-supported** |
| Size | 14 MB | 8 MB |
| Requires iOS | **17.0** | 18.6 |
| Devices | iPhone | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [志勇 杨](https://appshunter.io/developer/1137372489) | [Marc L. Melcher](https://appshunter.io/developer/371961192) |

## What reviewers say

### Rock Identifier

[App page](https://appshunter.io/ios/app/rock-identifier-stone-id/id6755675894)

Instantly identify rocks, crystals, and minerals by taking or uploading a photo. Get detailed geological information, track your discoveries in a digital journal, and learn about their formation and uses. Perfect for collectors, students, and anyone curious about stones.

**Highlights:** Instant photo identification, Detailed geological data, Mineral collection journal, Field identification techniques, Formation and usage information, Regional smart distribution

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| One Week - 3 Days Free Trial | $2.99 | per 7 days |
| One Week | $4.99 | per 7 days |
| One Year | $14.99 | per year |


### Space Arc

[App page](https://appshunter.io/ios/app/space-arc/id6759466047)

Explore celestial events with real-time data from NASA and other space agencies. Track satellites, view stunning astronomy pictures, and get personalized alerts for meteor showers, eclipses, and aurora.

**Highlights:** Real-time satellite tracking, NASA Picture of the Day, Global launch calendar, Celestial events calendar, Aurora alerts, Smart notifications, Offline event caching

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Rock Identifier free?

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

### Is Space Arc free?

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

### Which has better reviews, Rock Identifier or Space Arc?

Space Arc is rated higher. Rock Identifier averages 4.8 out of 5 from 4 ratings, while Space Arc averages 5.0 from 3 ratings.

### Do Rock Identifier or Space Arc have ads?

Space Arc shows ads; Rock Identifier does not.

### Which is updated more often, Rock Identifier or Space Arc?

Rock Identifier ships an update every 5 months, and Space Arc monthly. Most recently, Rock Identifier was updated on October 30, 2026 and Space Arc 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.*