# Thread Chart vs Rock Identifier | Stone ID

The clearest difference is in-app purchases: Thread Chart at none against Rock Identifier | Stone ID's 3. Thread Chart also leads on iOS requirement (8.0 vs 15.0). Rock Identifier | Stone ID's advantage is device support. On price there is nothing between them.

Both are free to download. Rock Identifier | Stone ID sells 3 in-app purchases, starting at $4.99 per 7 days. Thread Chart asks for nothing beyond the download.

## The numbers

| Metric | Thread Chart | Rock Identifier | Stone ID |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.0 (2 ratings)](https://appshunter.io/ios/app/thread-chart/id1335115083/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | — | No |
| Monetization | **Free** | Freemium |
| Size | 16 MB | 61 MB |
| Requires iOS | **8.0** | 15.0 |
| Devices | — | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Igor Pivnyk](https://appshunter.io/developer/1335115082) | [DIDEM URAS](https://appshunter.io/developer/1896691187) |

## What reviewers say

### Thread Chart

[App page](https://appshunter.io/ios/app/thread-chart/id1335115083)

This app provides machinists with quick access to screw thread tolerances for various ISO and UN threads, including exotic sizes. It supports internal and external threads and calculates tap holes, eliminating the need for tolerance tables.

**Highlights:** ISO and UN thread tolerance processing, Support for exotic thread sizes, Internal and external thread calculations, Tap hole calculation, Eliminates need for tolerance tables

**In-app purchases:** none


### Rock Identifier | Stone ID

[App page](https://appshunter.io/ios/app/rock-identifier-stone-id/id6772498820)

Identify rocks, minerals, crystals, and fossils instantly with a photo. Get scientific data, market value estimates, and track your collection. Explore the earth's secrets with this geological lab in your pocket.

**Highlights:** Instant photo identification, Real-time value estimator, Comprehensive geological data, Interactive crystal guide, Personal collection tracker, Similar specimen finder

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Plan | $4.99 | per 7 days |
| Yearly Plan | $39.99 | per year |
| Lifetime Plan | $79.99 | one-time |


## Frequently asked questions

### Is Thread Chart free?

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

### Is Rock Identifier | Stone ID free?

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

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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.*