# CastReader vs Synapse

The clearest difference is in-app purchases: Synapse at none against CastReader's 5. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. CastReader sells 5 in-app purchases, starting at $4.99 per month. Synapse asks for nothing beyond the download.

Both ship on a similar rhythm, roughly every 2 days. The most recent releases landed on October 28, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | CastReader | Synapse |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (41 ratings)](https://appshunter.io/ios/app/castreader-read-aloud-books/id6757636395/reviews)** | — |
| Number of ratings | **41** | — |
| Positive reviews | 96.8% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 2 days | Every 2 days |
| Monetization | Free | — |
| Size | 164 MB | 181 MB |
| Requires iOS | 17.6 | **17** |
| Devices | **iPhone, iPad, Mac** | iPhone, iPad |
| Age rating | 4+ | 12+ |
| Developer | [ohsame Inc](https://appshunter.io/developer/944872977) | [Mattia Capomagi](https://appshunter.io/developer/1895857137) |

## What reviewers say

### CastReader

[App page](https://appshunter.io/ios/app/castreader-read-aloud-books/id6757636395)

This app transforms your reading into an audio experience with natural voices and synced highlighting. It offers AI-powered explanations for complex passages, making difficult texts easier to understand. Listen to books, documents, and web pages while on the go.

**Highlights:** Listen to Kindle books, PDFs, EPUBs, AI explanations for complex text, Synced highlighting with read-aloud, Auto-scroll and resume progress, Background and lock-screen playback, Supports web pages, photos, and pasted text

**Features:** Safari Extension, Vision Pro support, iPhone Duo support

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| CastReader Pro (Monthly) | $4.99 | per month |
| CastReader Pro (Monthly) | $9.99 | per month |
| CastReader Pro (Yearly) | $34.99 | per year |
| CastReader Pro (Yearly) | $59.99 | per year |
| 120 Clone Voice Minutes | $2.99 | one-time |


### Synapse

[App page](https://appshunter.io/ios/app/synapse-daily-knowledge/id6764631049)

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

**In-app purchases:** none


## Frequently asked questions

### Is CastReader free?

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

### Is Synapse free?

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

### Do CastReader or Synapse have ads?

Neither CastReader nor Synapse shows ads.

### Which is updated more often, CastReader or Synapse?

CastReader ships an update every 2 days, and Synapse every 2 days. Most recently, CastReader was updated on October 28, 2026 and Synapse on October 25, 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.*