# O-Ring — user reviews

> 12 indexed App Store user reviews of O by Trelleborg Sealing Solutions, rated 3.80/5 from 5 ratings.

- Source: https://appshunter.io/ios/app/o-ring/id485346224/reviews
- App overview in markdown: https://appshunter.io/ios/app/o-ring/id485346224.md
- Rating breakdown: 5★ 3 · 4★ 0 · 3★ 1 · 2★ 0 · 1★ 1

## Most critical reviews (10 lowest-rated)

### 1/5 — Useless

*2024-08-03, version 4.4*

Unfortunately useless 
Don’t bother with it

### 2/5 — App not working

*2014-11-22, version 2.5*

I've just found out the latest app does not open on my iPod touch running IOS 5.1.1 (earlier ones worked ok)
It works fine on my iPad which is running the latest operating system.
I can't see any comments that state it wouldn't work on the iPod but even after removing it and downloading it again it's still not opening.
Normally apps won't download if the wrong version operating system is running. Does anyone have any ideas?
Thanks,
John.

### 5/5 — Great app!

*2012-10-22, version 1.3*

Really useful app for specifying o-rings. Almost as good as Trelleborg's superb web based o-ring calculator.

### 5/5 — Great Tool For Engineers

*2012-01-23*

As a mechanical engineer, I find this app very useful. I use it at least once a week. The layout of the app is very easy to work with and intuitive. A must have app for all engineers and for anyone who works with o-rings. Thanks Trelleborg for spending the time on this app.

### 5/5 — Quick reference.

*2012-01-18*

This is a great tool for quickly calculating o-ring sizes. I've mostly used the "quick search" to determine standard sizes.

### 5/5 — Another awesome app from Trelleborg

*2012-01-17*

Great time saver!

### 5/5 — O-ring tool

*2012-01-17*

This is a great tool for quick answers on the go.

### 5/5 — Sales

*2012-01-17*

Excellent tool & reference guide. Extensive fluid compatibility chart as well. Very helpful!!

### 5/5 — Everything I need at my fingertips

*2012-01-17*

Also good for unit conversion

### 5/5 — Sales

*2012-01-17*

Great application

## Most praised reviews (2 highest-rated)

### 5/5 — Engineer

*2012-01-17*

Great App! Really like the Material vs. Chemical Compatibility chart.

### 5/5 — Mech Engineer

*2011-12-10*

A great tool to keep you from having to look through pages and pages of catalogs.

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-04.*