# STS2 vs PDF Library & Reader

The clearest difference is in-app purchases: STS2 at none against PDF Library & Reader's 1. STS2 also leads on iOS requirement (13.0 vs 15.0). On price, ads and device support there is nothing between them.

Both are free to download. PDF Library & Reader sells 1 one-off in-app purchase. STS2 asks for nothing beyond the download.

## The numbers

| Metric | STS2 | PDF Library & Reader |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (2 ratings)](https://appshunter.io/ios/app/pdf-library-and-reader/id6752359955/reviews)** |
| Number of ratings | — | **2** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | — |
| Monetization | — | Free with in-app purchases |
| Size | 76 MB | 1 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [中铁工程装备集团有限公司](https://appshunter.io/developer/1447605449) | [Wildcatter LLC](https://appshunter.io/developer/1229934042) |

## What reviewers say

### STS2

[App page](https://appshunter.io/ios/app/sts2/id6444602139)

**Features:** Vision Pro support

**In-app purchases:** none


### PDF Library & Reader

[App page](https://appshunter.io/ios/app/pdf-library-and-reader/id6752359955)

A minimalist, offline PDF reader allowing users to import documents, track reading progress, and organize their library. It offers a distraction-free reading experience with no signup or internet required.

**Highlights:** Import PDFs from various sources, Automatic reading progress saving, Customizable book titles, Reset reading progress, Offline functionality, Distraction-free reading

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PDF Library Pro | $9.99 | one-time |


## Frequently asked questions

### Is STS2 free?

STS2 is free to download, with no in-app purchases.

### Is PDF Library & Reader free?

PDF Library & Reader is free to download, with in-app purchases available.

### Do STS2 or PDF Library & Reader have ads?

Neither STS2 nor PDF Library & Reader shows ads.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*