# PDF Dark vs GymOS

The clearest difference is price: GymOS at Free against PDF Dark's $3.99. GymOS also leads on iOS requirement (15.1 vs 17.6). On ads, in-app purchases and device support there is nothing between them.

GymOS is free to download; PDF Dark costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

## The numbers

| Metric | PDF Dark | GymOS |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | **[4.0 (2 ratings)](https://appshunter.io/ios/app/pdf-dark/id6470178025/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 25.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 11 months | — |
| Monetization | Paid | — |
| Size | 1 MB | 50 MB |
| Requires iOS | 17.6 | **15.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 17+ |
| Developer | [Jorge Lucioni Charalla](https://appshunter.io/developer/1198674844) | [Ebenezer Amaraiwu](https://appshunter.io/developer/1833647690) |

## What reviewers say

### PDF Dark

[App page](https://appshunter.io/ios/app/pdf-dark/id6470178025)

Transform bright PDF pages into a comfortable dark mode for easier reading at night. Reduce eye strain, improve focus, and potentially save battery life. Enjoy a smoother reading experience on your devices.

**Highlights:** Dark mode for PDFs, Reduced eye strain, Improved focus, Battery saving, Multi-device support

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

**In-app purchases:** none


### GymOS

[App page](https://appshunter.io/ios/app/gymos/id6755928065)

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

**In-app purchases:** none


## Frequently asked questions

### Is PDF Dark free?

PDF Dark costs $3.99, with no in-app purchases.

### Is GymOS free?

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

### Do PDF Dark or GymOS have ads?

Neither PDF Dark nor GymOS shows ads.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*