# Curso ISB vs RAIO App

The clearest difference is rating: Curso ISB at 3.5 against RAIO App's 2.7. Curso ISB also leads on in-app purchases (none vs 2) and iOS requirement (13.6 vs 15.0). RAIO App's advantage is review sentiment (20% vs 0%) and update cadence (every 6 weeks vs every 3 months). On price, ads and device support there is nothing between them.

Both are free to download. RAIO App sells 2 in-app purchases, starting at $19.99 per month. Curso ISB asks for nothing beyond the download.

Curso ISB holds the better App Store score, 3.5 against 2.7. Both are backed by a comparable volume of ratings — 13 and 43 respectively. Written reviews complicate that: 0% of Curso ISB's written reviews are positive against 20% of RAIO App's, so the app with the better star average is not the one people write more warmly about.

Curso ISB ships an update every 3 months, RAIO App every 6 weeks. The most recent releases landed on October 23, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Curso ISB | RAIO App |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.5 (13 ratings)](https://appshunter.io/ios/app/curso-isb/id1593090606/reviews)** | [2.7 (43 ratings)](https://appshunter.io/ios/app/raio-app/id6446694876/reviews) |
| Number of ratings | 13 | **43** |
| Positive reviews | 0.0% of reviews | **20.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 6 weeks** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 158 MB | 88 MB |
| Requires iOS | **13.6** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Telsur Inc.](https://appshunter.io/developer/1593090608) | [Kale Anders](https://appshunter.io/developer/1678765749) |

## What reviewers say

### Curso ISB

[App page](https://appshunter.io/ios/app/curso-isb/id1593090606)

This app offers online English classes led by qualified teachers. Engage in interactive lessons and improve your language skills from anywhere. It provides a convenient platform for structured English learning.

**Highlights:** Online English classes, Qualified teachers, Interactive lessons, Language skill improvement, Convenient learning platform

**Features:** macOS Compatibility

**In-app purchases:** none


### RAIO App

[App page](https://appshunter.io/ios/app/raio-app/id6446694876)

This app uses spaced repetition technology and real-life sentences to help you learn grammar and vocabulary in context. It aims to improve retention, reduce translation in your head, and help you start thinking in the language you're learning.

**Highlights:** Spaced repetition technology, Sentence-based learning, Learn grammar and vocabulary in context, Reduce translation in your head, Think in the target language, Personalized progress reports, Gamification features

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly - Standard Plan | $19.99 | per month |
| Annual - SAVE 20%! | $179.99 | per year |


## Frequently asked questions

### Is Curso ISB free?

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

### Is RAIO App free?

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

### Which has better reviews, Curso ISB or RAIO App?

Curso ISB is rated higher. Curso ISB averages 3.5 out of 5 from 13 ratings, while RAIO App averages 2.7 from 43 ratings.

### Do Curso ISB or RAIO App have ads?

Neither Curso ISB nor RAIO App shows ads.

### Which is updated more often, Curso ISB or RAIO App?

Curso ISB ships an update every 3 months, and RAIO App every 6 weeks. Most recently, Curso ISB was updated on October 23, 2026 and RAIO App on October 24, 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.*