# Sub System vs EHE Ethical Hacking Exam Prep

The clearest difference is price: EHE Ethical Hacking Exam Prep at Free against Sub System's $30.00. Sub System's advantage is in-app purchases (none vs 3) and update cadence (every 10 days vs every 4 months). On ads and device support there is nothing between them.

EHE Ethical Hacking Exam Prep is free to download; Sub System costs $30.00 up front. EHE Ethical Hacking Exam Prep sells 3 in-app purchases, starting at $3.99 per month. Sub System asks for nothing beyond the download.

Sub System ships an update every 10 days, EHE Ethical Hacking Exam Prep every 4 months. The most recent releases landed on October 7, 2026 and October 2, 2026 respectively.

## The numbers

| Metric | Sub System | EHE Ethical Hacking Exam Prep |
| --- | --- | --- |
| Price | $30.00 | **Free** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 10 days** | Every 4 months |
| Monetization | Paid | — |
| Size | 48 MB | 26 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [sebastian rivas](https://appshunter.io/developer/506708461) | [Davy Raitt](https://appshunter.io/developer/1795318281) |

## What reviewers say

### Sub System

[App page](https://appshunter.io/ios/app/sub-system/id1533524994)

This app allows audio engineers and sound designers to visualize sound pressure levels and their interactions. Users can place virtual speakers and microphones, manipulate them with touch gestures, and observe colorful graphs of SPL and frequency response to understand acoustical summation.

**Highlights:** Virtual speaker placement, Sound pressure level visualization, Frequency response graphs, Virtual microphone simulation, Touch-based manipulation, Acoustical summation understanding

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

**In-app purchases:** none


### EHE Ethical Hacking Exam Prep

[App page](https://appshunter.io/ios/app/ehe-ethical-hacking-exam-prep/id6758674929)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly | $3.99 | per month |
| Pro Yearly | $14.99 | per year |
| Pro Lifetime | $19.99 | one-time |


## Frequently asked questions

### Is Sub System free?

Sub System costs $30.00, with no in-app purchases.

### Is EHE Ethical Hacking Exam Prep free?

EHE Ethical Hacking Exam Prep is free to download, with in-app purchases available.

### Do Sub System or EHE Ethical Hacking Exam Prep have ads?

Neither Sub System nor EHE Ethical Hacking Exam Prep shows ads.

### Which is updated more often, Sub System or EHE Ethical Hacking Exam Prep?

Sub System ships an update every 10 days, and EHE Ethical Hacking Exam Prep every 4 months. Most recently, Sub System was updated on October 7, 2026 and EHE Ethical Hacking Exam Prep on October 2, 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.*