# PDF Under vs Compress PDF

The clearest difference is in-app purchases: Compress PDF at none against PDF Under's 3. Compress PDF also leads on update cadence (every 4 days vs every 3 weeks). PDF Under's advantage is ads (none vs shown). On price, device support and iOS requirement there is nothing between them.

Both are free to download. PDF Under sells 3 in-app purchases, starting at $1.99 per 7 days. Compress PDF asks for nothing beyond the download.

PDF Under ships an update every 3 weeks, Compress PDF every 4 days. The most recent releases landed on October 25, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | PDF Under | Compress PDF |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | Every 3 weeks | **Every 4 days** |
| Size | 3 MB | 14 MB |
| Requires iOS | **17.6** | 18.0 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Emre KABOGLU](https://appshunter.io/developer/1892627286) | [Bokeria](https://appshunter.io/developer/1425332310) |

## What reviewers say

### PDF Under

[App page](https://appshunter.io/ios/app/pdf-under-pdf-compressor/id6804278677)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PDF Under Weekly | $1.99 | per 7 days |
| PDF Under Yearly | $13.99 | per year |
| PDF Under Lifetime | $19.99 | one-time |


### Compress PDF

[App page](https://appshunter.io/ios/app/compress-pdf-shrink-file/id6815961848)

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

**In-app purchases:** none


## Frequently asked questions

### Is PDF Under free?

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

### Is Compress PDF free?

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

### Do PDF Under or Compress PDF have ads?

Compress PDF shows ads; PDF Under does not.

### Which is updated more often, PDF Under or Compress PDF?

PDF Under ships an update every 3 weeks, and Compress PDF every 4 days. Most recently, PDF Under was updated on October 25, 2026 and Compress PDF 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.*