# O vs The Phillips Machinist

The clearest difference is rating: The Phillips Machinist at 4.6 against O's 3.8. The Phillips Machinist also leads on ratings volume (394 vs 5) and iOS requirement (15.6 vs 26.0). O's advantage is ads (none vs shown) and monetization model (free vs free with in-app purchases). On price, review sentiment, update cadence 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.

The Phillips Machinist holds the better App Store score, 4.6 against 3.8. That said, the two scores are not equally well evidenced: The Phillips Machinist has 394 ratings behind it against 5, so its average is the more settled of the two. Written reviews complicate that: 83% of O's written reviews are positive against 78% of The Phillips Machinist's, so the app with the better star average is not the one people write more warmly about.

O ships an update every 3 months, The Phillips Machinist every 6 weeks. Both last shipped on November 2, 2026.

## The numbers

| Metric | O | The Phillips Machinist |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.8 (5 ratings)](https://appshunter.io/ios/app/o-ring/id485346224/reviews) | **[4.6 (394 ratings)](https://appshunter.io/ios/app/the-phillips-machinist/id1046408069/reviews)** |
| Number of ratings | 5 | **394** |
| Positive reviews | **83.3% of reviews** | 78.3% of reviews |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 3 months | **Every 6 weeks** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 35 MB | 152 MB |
| Requires iOS | 26.0 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Trelleborg Sealing Solutions](https://appshunter.io/developer/396863758) | [Phillips Corporation](https://appshunter.io/developer/1141872391) |

## What reviewers say

### O

[App page](https://appshunter.io/ios/app/o-ring/id485346224)

This app helps users calculate O-ring dimensions and find suitable O-ring sizes based on installation specifications. It supports metric and inch measurements and offers chemical compatibility checks for various media.

**Highlights:** O-Ring housing calculation, O-Ring size recommendation, Quick search by international standards, Tolerance calculation, Metric and inch unit switching, Chemical compatibility check

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

**In-app purchases:** none


### The Phillips Machinist

[App page](https://appshunter.io/ios/app/the-phillips-machinist/id1046408069)

Access essential machine codes, calculators, and practical resources for machinists. Get direct support from engineers and explore a library of machining information. Enhance your productivity and problem-solving on the shop floor.

**Highlights:** Haas G & M reference codes, Error and Alarm Codes, Calculator library (Inch/Metric), Speeds & Feeds calculator, Direct contact with engineers, Customizable machine and interest tracking, FAQ library

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

**In-app purchases:** none

**What reviewers like**

- 👍 Easy to navigate
- 👍 Comprehensive information
- 👍 Great for machinists
- 👍 Useful for school and work
- 👍 Handy resource

**What reviewers complain about**

- 🐛 White screen on calculator
- 🐛 Speeds and feeds calculator not working
- 🐛 Unable to sign in
- 🐛 App crashes instantly
- 🐛 No volume on videos

**Reported bugs**

- Cannot sign in via Apple
- Password incorrect error
- Cannot reset password
- White screen on speed and feeds calculator (iPhone)
- Speeds and feeds calculator boxes not proper

**Requested features**

- Fix sign-in issues
- Resolve white screen on calculator
- Enable offline functionality
- Add volume to videos


## Frequently asked questions

### Is O free?

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

### Is The Phillips Machinist free?

The Phillips Machinist is free to download, with no in-app purchases.

### Which has better reviews, O or The Phillips Machinist?

The Phillips Machinist is rated higher. O averages 3.8 out of 5 from 5 ratings, while The Phillips Machinist averages 4.6 from 394 ratings.

### Do O or The Phillips Machinist have ads?

The Phillips Machinist shows ads; O does not.

### Which is updated more often, O or The Phillips Machinist?

O ships an update every 3 months, and The Phillips Machinist every 6 weeks. Most recently, O was updated on November 2, 2026 and The Phillips Machinist on November 2, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*