# I.S. 584 vs Robin

The clearest difference is in-app purchases: I.S. 584 at none against Robin's 4. I.S. 584 also leads on ads (none vs shown). Robin's advantage is update cadence (every 5 days vs every 2 months). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Robin sells 4 in-app purchases, starting at $2.99 per 7 days. I.S. 584 asks for nothing beyond the download.

I.S. 584 ships an update every 2 months, Robin every 5 days. The most recent releases landed on October 12, 2026 and September 16, 2026 respectively.

## The numbers

| Metric | I.S. 584 | Robin |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 2 months | **Every 5 days** |
| Size | 163 MB | 297 MB |
| Requires iOS | 15.6 | **14.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Solved Education Consultancy, LLC](https://appshunter.io/developer/1506645558) | [Word Search Games A.S](https://appshunter.io/developer/1721348806) |

## What reviewers say

### I.S. 584

[App page](https://appshunter.io/ios/app/is-584/id1613989382)

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

**In-app purchases:** none


### Robin

[App page](https://appshunter.io/ios/app/robin-brain-training/id6502344994)

**Features:** macOS Compatibility

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Subscription | $2.99 | per 7 days |
| Weekly Subscription | $4.99 | per 7 days |
| Yearly Subscription | $39.99 | per year |
| Lifetime Pro | $49.90 | one-time |


## Frequently asked questions

### Is I.S. 584 free?

I.S. 584 is free to download, with no in-app purchases.

### Is Robin free?

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

### Do I.S. 584 or Robin have ads?

Robin shows ads; I.S. 584 does not.

### Which is updated more often, I.S. 584 or Robin?

I.S. 584 ships an update every 2 months, and Robin every 5 days. Most recently, I.S. 584 was updated on October 12, 2026 and Robin on September 16, 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.*