# Cambridge Proficiency C2 Prep vs Chemicastle

The clearest difference is price: Chemicastle at Free against Cambridge Proficiency C2 Prep's $24.99. Chemicastle also leads on update cadence (every 4 months vs every 39 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

Chemicastle is free to download; Cambridge Proficiency C2 Prep costs $24.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Cambridge Proficiency C2 Prep ships an update every 39 months, Chemicastle every 4 months. The most recent releases landed on October 12, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Cambridge Proficiency C2 Prep | Chemicastle |
| --- | --- | --- |
| Price | $24.99 | **Free** |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 39 months | **Every 4 months** |
| Monetization | Paid | — |
| Size | 7 MB | 301 MB |
| Requires iOS | 16.6 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 17+ | 9+ |
| Developer | [Aidan Michael Casey](https://appshunter.io/developer/916717333) | [Haute ecole pedagogique HEP-BEJUNE](https://appshunter.io/developer/1835648343) |

## What reviewers say

### Cambridge Proficiency C2 Prep

[App page](https://appshunter.io/ios/app/cambridge-proficiency-c2-prep/id1668057092)

This app offers targeted practice for the revised Cambridge Proficiency Exam. It focuses on four key English language skills through interactive units, video presentations, and sample questions. Designed for exam preparation, it covers collocations, grammar, word formation, and paraphrasing.

**Highlights:** Covers four Use Of English exam tasks, Focuses on collocations, grammar, word formation, paraphrasing, Includes video presentations, Offers practice activities and sample exam questions, Provides notes on language, meaning, and usage, Material for 30-50 hours of study

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

**In-app purchases:** none


### Chemicastle

[App page](https://appshunter.io/ios/app/chemicastle/id6753705536)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Cambridge Proficiency C2 Prep free?

Cambridge Proficiency C2 Prep costs $24.99, with no in-app purchases.

### Is Chemicastle free?

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

### Do Cambridge Proficiency C2 Prep or Chemicastle have ads?

Neither Cambridge Proficiency C2 Prep nor Chemicastle shows ads.

### Which is updated more often, Cambridge Proficiency C2 Prep or Chemicastle?

Cambridge Proficiency C2 Prep ships an update every 39 months, and Chemicastle every 4 months. Most recently, Cambridge Proficiency C2 Prep was updated on October 12, 2026 and Chemicastle on October 24, 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.*