# ZKBio Zlink vs Black Reader

The clearest difference is in-app purchases: ZKBio Zlink at none against Black Reader's 1. Black Reader's advantage is update cadence (every 3 days vs every 3 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Black Reader sells 1 one-off in-app purchase. ZKBio Zlink asks for nothing beyond the download.

ZKBio Zlink ships an update every 3 weeks, Black Reader every 3 days. The most recent releases landed on October 16, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | ZKBio Zlink | Black Reader |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/zkbio-zlink/id1640267070/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 3 days** |
| Monetization | Free | — |
| Size | 207 MB | 31 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [ZKTeco Inc.](https://appshunter.io/developer/955313767) | [ZAKARIA ELAROUSSI](https://appshunter.io/developer/1895555101) |

## What reviewers say

### ZKBio Zlink

[App page](https://appshunter.io/ios/app/zkbio-zlink/id1640267070)

This cloud-based IoT platform integrates access control, time and attendance, and an approval center for small to medium-sized businesses. It enhances operational efficiency and connectivity, offering a scalable solution without significant upfront IT investment.

**Highlights:** Cloud-based IoT platform, Integrated access control, Time and attendance tracking, Approval center, Scalable AWS infrastructure, Simplified operations

**In-app purchases:** none


### Black Reader

[App page](https://appshunter.io/ios/app/black-reader-pdf-reader/id6800425465)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Black Reader PRO | $0.99 | one-time |


## Frequently asked questions

### Is ZKBio Zlink free?

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

### Is Black Reader free?

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

### Do ZKBio Zlink or Black Reader have ads?

Neither ZKBio Zlink nor Black Reader shows ads.

### Which is updated more often, ZKBio Zlink or Black Reader?

ZKBio Zlink ships an update every 3 weeks, and Black Reader every 3 days. Most recently, ZKBio Zlink was updated on October 16, 2026 and Black Reader on October 8, 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.*