# ISBN vs SlowRead

The clearest difference is in-app purchases: ISBN at none against SlowRead's 2. SlowRead's advantage is ads (none vs shown) and update cadence (fortnightly vs every 4 months). On price, device support and iOS requirement there is nothing between them.

Both are free to download. SlowRead sells 2 in-app purchases, starting at $3.99 per month. ISBN asks for nothing beyond the download.

ISBN ships an update every 4 months, SlowRead fortnightly. The most recent releases landed on October 2, 2026 and September 29, 2026 respectively.

## The numbers

| Metric | ISBN | SlowRead |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 4 months | **Fortnightly** |
| Size | 16 MB | 66 MB |
| Requires iOS | **14.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [剑秋 肖](https://appshunter.io/developer/806037264) | [T-PLUS Ltd](https://appshunter.io/developer/1881859700) |

## What reviewers say

### ISBN

[App page](https://appshunter.io/ios/app/isbn/id6449743934)

**Features:** macOS Compatibility

**In-app purchases:** none


### SlowRead

[App page](https://appshunter.io/ios/app/slowread/id6759947443)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| SlowRead Pro | $3.99 | per month |
| SlowRead Pro | $29.99 | per year |


## Frequently asked questions

### Is ISBN free?

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

### Is SlowRead free?

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

### Do ISBN or SlowRead have ads?

ISBN shows ads; SlowRead does not.

### Which is updated more often, ISBN or SlowRead?

ISBN ships an update every 4 months, and SlowRead fortnightly. Most recently, ISBN was updated on October 2, 2026 and SlowRead on September 29, 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.*