# O vs Olypsys Measure

The clearest difference is rating: O at 5.0 against Olypsys Measure's 3.0. O also leads on in-app purchases (none vs 3). Olypsys Measure's advantage is update cadence (every 4 weeks vs every 11 months) and ratings volume (4 vs 1). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Olypsys Measure sells 3 in-app purchases, starting at $10.00 per month. O asks for nothing beyond the download.

O holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 1 and 4 respectively.

O ships an update every 11 months, Olypsys Measure every 4 weeks. The most recent releases landed on September 22, 2026 and September 17, 2026 respectively.

## The numbers

| Metric | O | Olypsys Measure |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/o-ring-master/id1072051820/reviews)** | [3.0 (4 ratings)](https://appshunter.io/ios/app/olypsys-measure/id1583943944/reviews) |
| Number of ratings | 1 | **4** |
| Positive reviews | — | 66.7% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 11 months | **Every 4 weeks** |
| Monetization | **Free** | Freemium |
| Size | 47 MB | 101 MB |
| Requires iOS | **16.0** | 16.4 |
| Devices | iPhone | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [GE MAO RUBBER INDUSTRIAL CO., LTD.](https://appshunter.io/developer/1078558543) | [Olypsys Technologies Ltd](https://appshunter.io/developer/1583943946) |

## What reviewers say

### O

[App page](https://appshunter.io/ios/app/o-ring-master/id1072051820)

This app provides a comprehensive offline tool for selecting standard rubber seal sizes, including O-Rings, X-Rings, and Back-Up Rings. It offers dimension searches, housing calculations for various sealing applications, and supports multiple international standards in both metric and imperial units.

**Highlights:** Offline standard rubber seal size selection, Search for O-Ring, X-Ring, and Back-Up Ring sizes, O-Ring housing calculations for sealing applications, Supports multiple international standards (AS568, METRIC, JIS, etc.), Metric and Imperial unit support, Substitutable O-Ring size suggestions

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

**In-app purchases:** none


### Olypsys Measure

[App page](https://appshunter.io/ios/app/olypsys-measure/id1583943944)

This app helps businesses accurately measure and identify O-rings using their phone. It matches measurements against international standards and maintains an audit record with project details. Ideal for quality control during goods-inward inspection, part replacement, and pre-assembly checks.

**Highlights:** Accurate O-ring measurement, O-ring identification, Match against international standards, Audit record keeping, Project reference and location tagging, Goods-inward inspection tool

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Olypsys Pro Monthly | $10.00 | per month |
| Pro (yearly) | $80.00 | per year |
| Olypsys Enterprise Yearly | $600.00 | per year |


## Frequently asked questions

### Is O free?

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

### Is Olypsys Measure free?

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

### Which has better reviews, O or Olypsys Measure?

O is rated higher. O averages 5.0 out of 5 from 1 ratings, while Olypsys Measure averages 3.0 from 4 ratings.

### Do O or Olypsys Measure have ads?

Neither O nor Olypsys Measure shows ads.

### Which is updated more often, O or Olypsys Measure?

O ships an update every 11 months, and Olypsys Measure every 4 weeks. Most recently, O was updated on September 22, 2026 and Olypsys Measure on September 17, 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.*