# Vacuum Link vs PDFDarkMode

The clearest difference is in-app purchases: Vacuum Link at none against PDFDarkMode's 6. Vacuum Link also leads on iOS requirement (8.0 vs 15.0). PDFDarkMode's advantage is update cadence (every 4 days vs every 18 months). On price, ads and device support there is nothing between them.

Both are free to download. PDFDarkMode sells 5 one-off in-app purchases. Vacuum Link asks for nothing beyond the download.

Vacuum Link ships an update every 18 months, PDFDarkMode every 4 days. The most recent releases landed on October 10, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Vacuum Link | PDFDarkMode |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/pdfdarkmode-customize-pdfs/id6744872327/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 18 months | **Every 4 days** |
| Monetization | — | Free with in-app purchases |
| Size | 65 MB | 4 MB |
| Requires iOS | **8.0** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Agilent Technologies, Inc](https://appshunter.io/developer/355827609) | [Wildcatter LLC](https://appshunter.io/developer/1229934042) |

## What reviewers say

### Vacuum Link

[App page](https://appshunter.io/ios/app/vacuum-link/id1457811255)

**In-app purchases:** none


### PDFDarkMode

[App page](https://appshunter.io/ios/app/pdfdarkmode-customize-pdfs/id6744872327)

Easily convert PDFs to a comfortable dark mode with custom text and background colors. Reduce eye strain while reading or studying long documents. Save and revisit your personalized PDFs in a private library.

**Highlights:** Upload PDFs from device, Customize text and background colors, Preview dark mode changes, Download converted PDFs, Personal PDF library, Private by design

**Features:** macOS Compatibility

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Download PDF (up to 100 pages) | $0.99 | one-time |
| Dark Mode PDF Download | $2.99 | one-time |
| Download PDF (up to 500 pages) | $4.99 | one-time |
| PDFDarkMode Pro | $9.99 | one-time |
| Download PDF (500+ pages) | $9.99 | one-time |


## Frequently asked questions

### Is Vacuum Link free?

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

### Is PDFDarkMode free?

PDFDarkMode is free to download, with in-app purchases available.

### Do Vacuum Link or PDFDarkMode have ads?

Neither Vacuum Link nor PDFDarkMode shows ads.

### Which is updated more often, Vacuum Link or PDFDarkMode?

Vacuum Link ships an update every 18 months, and PDFDarkMode every 4 days. Most recently, Vacuum Link was updated on October 10, 2026 and PDFDarkMode on October 13, 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.*