# DiffOrologi vs iCatalogue 4

The clearest difference is update cadence: iCatalogue 4 at fortnightly against DiffOrologi's every 2 months. DiffOrologi's advantage is iOS requirement (11.0 vs 15.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

DiffOrologi ships an update every 2 months, iCatalogue 4 fortnightly. The most recent releases landed on September 26, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | DiffOrologi | iCatalogue 4 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Fortnightly** |
| Size | 30 MB | 76 MB |
| Requires iOS | **11.0** | 15.6 |
| Devices | iPad | iPad |
| Age rating | 4+ | 17+ |
| Developer | [DOING srl](https://appshunter.io/developer/423545481) | [Femar Consulting S.r.l.](https://appshunter.io/developer/393116092) |

## What reviewers say

### DiffOrologi

[App page](https://appshunter.io/ios/app/difforologi/id974960351)

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

**In-app purchases:** none


### iCatalogue 4

[App page](https://appshunter.io/ios/app/icatalogue-4/id1502720334)

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is DiffOrologi free?

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

### Is iCatalogue 4 free?

iCatalogue 4 is free to download, with no in-app purchases.

### Do DiffOrologi or iCatalogue 4 have ads?

Neither DiffOrologi nor iCatalogue 4 shows ads.

### Which is updated more often, DiffOrologi or iCatalogue 4?

DiffOrologi ships an update every 2 months, and iCatalogue 4 fortnightly. Most recently, DiffOrologi was updated on September 26, 2026 and iCatalogue 4 on October 3, 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.*