# PhiMasterClass vs StoneID Rock Identifier

The clearest difference is in-app purchases: PhiMasterClass at none against StoneID Rock Identifier's 3. PhiMasterClass also leads on update cadence (every 2 days vs every 6 months) and iOS requirement (11.0 vs 18.1). On price, ads and device support there is nothing between them.

Both are free to download. StoneID Rock Identifier sells 3 in-app purchases, starting at $3.99 per 7 days. PhiMasterClass asks for nothing beyond the download.

PhiMasterClass ships an update every 2 days, StoneID Rock Identifier every 6 months. The most recent releases landed on October 4, 2026 and September 29, 2026 respectively.

## The numbers

| Metric | PhiMasterClass | StoneID Rock Identifier |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[2.5 (2 ratings)](https://appshunter.io/ios/app/stoneid-rock-identifier/id6741160166/reviews)** |
| Number of ratings | — | **2** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 2 days** | Every 6 months |
| Monetization | — | Free with in-app purchases |
| Size | 66 MB | 88 MB |
| Requires iOS | **11.0** | 18.1 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Branko Babic](https://appshunter.io/developer/1231442637) | [Kesifler Dunyasi Ltd.](https://appshunter.io/developer/1173478543) |

## What reviewers say

### PhiMasterClass

[App page](https://appshunter.io/ios/app/phimasterclass/id1470586273)

**Features:** macOS Compatibility

**In-app purchases:** none


### StoneID Rock Identifier

[App page](https://appshunter.io/ios/app/stoneid-rock-identifier/id6741160166)

Identify rocks, stones, and gems using their scientific properties. Explore detailed descriptions, high-quality images, and advanced filters. Perfect for students, collectors, and outdoor enthusiasts interested in geology.

**Highlights:** Identify rocks by scientific properties, Filter and compare rocks by geological criteria, In-depth descriptions and high-quality images, Advanced scientific filters, Pocket geologist functionality

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Subscription | $3.99 | per 7 days |
| Monthly Subscription | $5.99 | per month |
| Annual Subscription | $9.99 | per year |


## Frequently asked questions

### Is PhiMasterClass free?

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

### Is StoneID Rock Identifier free?

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

### Do PhiMasterClass or StoneID Rock Identifier have ads?

Neither PhiMasterClass nor StoneID Rock Identifier shows ads.

### Which is updated more often, PhiMasterClass or StoneID Rock Identifier?

PhiMasterClass ships an update every 2 days, and StoneID Rock Identifier every 6 months. Most recently, PhiMasterClass was updated on October 4, 2026 and StoneID Rock Identifier on September 29, 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.*