# OCCDEC Occasion Detection vs FourScan

The clearest difference is update cadence: FourScan at every 5 days against OCCDEC Occasion Detection's every 2 weeks. OCCDEC Occasion Detection's advantage is device support (3 vs 1). On price, ads, in-app purchases and iOS requirement there is nothing between them.

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

OCCDEC Occasion Detection ships an update every 2 weeks, FourScan every 5 days. Both last shipped on October 29, 2026.

## The numbers

| Metric | OCCDEC Occasion Detection | FourScan |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 weeks | **Every 5 days** |
| Size | 32 MB | 3 MB |
| Requires iOS | **15.1** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [LineSpotting AB](https://appshunter.io/developer/1326519237) | [satoshi amasaki](https://appshunter.io/developer/1891268722) |

## What reviewers say

### OCCDEC Occasion Detection

[App page](https://appshunter.io/ios/app/occdec-occasion-detection/id1495592504)

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

**In-app purchases:** none


### FourScan

[App page](https://appshunter.io/ios/app/fourscan-spy-detector/id6761895107)

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

**In-app purchases:** none


## Frequently asked questions

### Is OCCDEC Occasion Detection free?

OCCDEC Occasion Detection is free to download, with no in-app purchases.

### Is FourScan free?

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

### Do OCCDEC Occasion Detection or FourScan have ads?

Neither OCCDEC Occasion Detection nor FourScan shows ads.

### Which is updated more often, OCCDEC Occasion Detection or FourScan?

OCCDEC Occasion Detection ships an update every 2 weeks, and FourScan every 5 days. Most recently, OCCDEC Occasion Detection was updated on October 29, 2026 and FourScan on October 29, 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.*