# SizeChina vs PolyU Library

The clearest difference is update cadence: PolyU Library at every 3 months against SizeChina's every 60 months. SizeChina's advantage is iOS requirement (12.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

SizeChina ships an update every 60 months, PolyU Library every 3 months. The most recent releases landed on October 11, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | SizeChina | PolyU Library |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 60 months | **Every 3 months** |
| Size | 23 MB | 35 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 17+ |
| Developer | [Apps Resource Centre, Hong Kong Baptist University](https://appshunter.io/developer/1375410542) | [The Hong Kong Polytechnic University](https://appshunter.io/developer/442903588) |

## What reviewers say

### SizeChina

[App page](https://appshunter.io/ios/app/sizechina/id1481186588)

**Features:** macOS Compatibility

**In-app purchases:** none


### PolyU Library

[App page](https://appshunter.io/ios/app/polyu-library/id6450161237)

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

**In-app purchases:** none


## Frequently asked questions

### Is SizeChina free?

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

### Is PolyU Library free?

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

### Do SizeChina or PolyU Library have ads?

Neither SizeChina nor PolyU Library shows ads.

### Which is updated more often, SizeChina or PolyU Library?

SizeChina ships an update every 60 months, and PolyU Library every 3 months. Most recently, SizeChina was updated on October 11, 2026 and PolyU Library on October 14, 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.*