# Luopan Placement Ruler vs PDFReader

The clearest difference is ads: Luopan Placement Ruler at none against PDFReader's shown. Luopan Placement Ruler also leads on update cadence (every 3 days vs every 2 months) and device support (3 vs 1). On price and in-app purchases there is nothing between them.

Both are free to download. Luopan Placement Ruler sells 1 one-off in-app purchase and PDFReader sells 2 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

Luopan Placement Ruler ships an update every 3 days, PDFReader every 2 months. The most recent releases landed on October 27, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | Luopan Placement Ruler | PDFReader |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 45.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Every 3 days** | Every 2 months |
| Size | 413 MB | 14 MB |
| Requires iOS | **15.6** | 18.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [CHEUNG PUI MAN](https://appshunter.io/developer/291179028) | [克 谢](https://appshunter.io/developer/1722475771) |

## What reviewers say

### Luopan Placement Ruler

[App page](https://appshunter.io/ios/app/luopan-placement-ruler/id412370642)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 数据无限保存 | $19.99 | one-time |


### PDFReader

[App page](https://appshunter.io/ios/app/pdfreader-ai-pdf-assistant/id6758230344)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Pro | $9.99 | per month |
| Yearly Pro | $49.99 | per year |


## Frequently asked questions

### Is Luopan Placement Ruler free?

Luopan Placement Ruler is free to download, with in-app purchases available.

### Is PDFReader free?

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

### Do Luopan Placement Ruler or PDFReader have ads?

PDFReader shows ads; Luopan Placement Ruler does not.

### Which is updated more often, Luopan Placement Ruler or PDFReader?

Luopan Placement Ruler ships an update every 3 days, and PDFReader every 2 months. Most recently, Luopan Placement Ruler was updated on October 27, 2026 and PDFReader on October 28, 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.*