# 甲子時空飛吊 vs PDFReader

The clearest difference is price: PDFReader at Free against 甲子時空飛吊's $11.99. 甲子時空飛吊's advantage is in-app purchases (none vs 2) and ads (none vs shown). On update cadence there is nothing between them.

PDFReader is free to download; 甲子時空飛吊 costs $11.99 up front. PDFReader sells 2 in-app purchases, starting at $9.99 per month. 甲子時空飛吊 asks for nothing beyond the download.

甲子時空飛吊 ships an update every 3 months, PDFReader every 2 months. The most recent releases landed on October 6, 2026 and October 9, 2026 respectively.

## The numbers

| Metric | 甲子時空飛吊 | PDFReader |
| --- | --- | --- |
| Price | $11.99 | **Free** |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 3 months | **Every 2 months** |
| Size | 58 MB | 14 MB |
| Requires iOS | **15.0** | 18.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [amtb fate](https://appshunter.io/developer/430174936) | [克 谢](https://appshunter.io/developer/1722475771) |

## What reviewers say

### 甲子時空飛吊

[App page](https://appshunter.io/ios/app/id1328280479)

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

**In-app purchases:** none


### 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 甲子時空飛吊 free?

甲子時空飛吊 costs $11.99, with no in-app purchases.

### Is PDFReader free?

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

### Do 甲子時空飛吊 or PDFReader have ads?

PDFReader shows ads; 甲子時空飛吊 does not.

### Which is updated more often, 甲子時空飛吊 or PDFReader?

甲子時空飛吊 ships an update every 3 months, and PDFReader every 2 months. Most recently, 甲子時空飛吊 was updated on October 6, 2026 and PDFReader on October 9, 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.*