# Sonic Motion vs ReadAid

The clearest difference is in-app purchases: Sonic Motion at none against ReadAid's 1. Sonic Motion also leads on iOS requirement (15.0 vs 26.1). ReadAid's advantage is update cadence (every 3 weeks vs every 15 months). On price, ads and device support there is nothing between them.

Both are free to download. ReadAid sells 1 in-app purchase, starting at $1.99 per month. Sonic Motion asks for nothing beyond the download.

Sonic Motion ships an update every 15 months, ReadAid every 3 weeks. The most recent releases landed on September 8, 2026 and September 19, 2026 respectively.

## The numbers

| Metric | Sonic Motion | ReadAid |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 15 months | **Every 3 weeks** |
| Size | 1 MB | 2 MB |
| Requires iOS | **15.0** | 26.1 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Yoshiyuki Koyanagi](https://appshunter.io/developer/1540530354) | [诗宇 梁](https://appshunter.io/developer/1868599151) |

## What reviewers say

### Sonic Motion

[App page](https://appshunter.io/ios/app/sonic-motion/id6736360866)

**Features:** macOS Compatibility

**In-app purchases:** none


### ReadAid

[App page](https://appshunter.io/ios/app/readaid/id6757760068)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ReadAid Pro | $1.99 | per month |


## Frequently asked questions

### Is Sonic Motion free?

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

### Is ReadAid free?

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

### Do Sonic Motion or ReadAid have ads?

Neither Sonic Motion nor ReadAid shows ads.

### Which is updated more often, Sonic Motion or ReadAid?

Sonic Motion ships an update every 15 months, and ReadAid every 3 weeks. Most recently, Sonic Motion was updated on September 8, 2026 and ReadAid on September 19, 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.*