# PIRS vs Unit Converter Superior

The clearest difference is update cadence: PIRS at every 3 months against Unit Converter Superior's every 21 months. PIRS also leads on iOS requirement (13.0 vs 15.0). 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.

PIRS ships an update every 3 months, Unit Converter Superior every 21 months. The most recent releases landed on October 26, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | PIRS | Unit Converter Superior |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 21 months |
| Size | 55 MB | 58 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [SOBIS Software GmbH](https://appshunter.io/developer/1294577493) | [Felix Peralta](https://appshunter.io/developer/1546086459) |

## What reviewers say

### PIRS

[App page](https://appshunter.io/ios/app/pirssite/id1230060880)

**Features:** macOS Compatibility

**In-app purchases:** none


### Unit Converter Superior

[App page](https://appshunter.io/ios/app/unit-converter-superior/id1630757981)

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

**In-app purchases:** none


## Frequently asked questions

### Is PIRS free?

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

### Is Unit Converter Superior free?

Unit Converter Superior is free to download, with no in-app purchases.

### Do PIRS or Unit Converter Superior have ads?

Neither PIRS nor Unit Converter Superior shows ads.

### Which is updated more often, PIRS or Unit Converter Superior?

PIRS ships an update every 3 months, and Unit Converter Superior every 21 months. Most recently, PIRS was updated on October 26, 2026 and Unit Converter Superior on October 30, 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.*