# 地震预警 vs PDF转换器

The clearest difference is update cadence: PDF转换器 at every 3 days against 地震预警's every 2 weeks. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. 地震预警 sells 1 one-off in-app purchase and PDF转换器 sells 2 in-app purchases, starting at $2.99 per 7 days. Whichever you choose, the download price is not the number that matters.

地震预警 ships an update every 2 weeks, PDF转换器 every 3 days. Both last shipped on October 30, 2026.

## The numbers

| Metric | 地震预警 | PDF转换器 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | **Every 3 days** |
| Size | 37 MB | 8 MB |
| Requires iOS | 15.6 | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [安波 张](https://appshunter.io/developer/1582565166) | [Ming Fai Lee](https://appshunter.io/developer/1691484255) |

## What reviewers say

### 地震预警

[App page](https://appshunter.io/ios/app/and/id6751939807)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 地震预警会员 | $5.99 | one-time |


### PDF转换器

[App page](https://appshunter.io/ios/app/pdf-pdf/id6755513544)

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PDF转换器周会员 | $2.99 | per 7 days |
| PDF转换器年会员 | $24.99 | per year |


## Frequently asked questions

### Is 地震预警 free?

地震预警 is free to download, with in-app purchases available.

### Is PDF转换器 free?

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

### Do 地震预警 or PDF转换器 have ads?

Neither 地震预警 nor PDF转换器 shows ads.

### Which is updated more often, 地震预警 or PDF转换器?

地震预警 ships an update every 2 weeks, and PDF转换器 every 3 days. Most recently, 地震预警 was updated on October 30, 2026 and PDF转换器 on October 30, 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.*