# OTRx vs ZIØN

The clearest difference is device support: OTRx at 3 against ZIØN's 1. OTRx also leads on iOS requirement (15.5 vs 17.0). On price, update cadence, ads and in-app purchases there is nothing between them.

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

OTRx ships an update every 6 weeks, ZIØN every 4 weeks. The most recent releases landed on October 8, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | OTRx | ZIØN |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Every 4 weeks** |
| Size | 129 MB | 2 MB |
| Requires iOS | **15.5** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [OTRx- SDM LLC](https://appshunter.io/developer/1850312441) | [Daniele Taormina](https://appshunter.io/developer/6786438542) |

## What reviewers say

### OTRx

[App page](https://appshunter.io/ios/app/otrx/id6754824269)

**In-app purchases:** none


### ZIØN

[App page](https://appshunter.io/ios/app/zin/id6786438540)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is OTRx free?

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

### Is ZIØN free?

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

### Do OTRx or ZIØN have ads?

Neither OTRx nor ZIØN shows ads.

### Which is updated more often, OTRx or ZIØN?

OTRx ships an update every 6 weeks, and ZIØN every 4 weeks. Most recently, OTRx was updated on October 8, 2026 and ZIØN on October 6, 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.*