# 素伊OM vs Pipe Diameter Calculators

The clearest difference is in-app purchases: 素伊OM at none against Pipe Diameter Calculators's 1. 素伊OM also leads on update cadence (every 6 weeks vs every 20 months). Pipe Diameter Calculators's advantage is ads (none vs shown). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Pipe Diameter Calculators sells 1 one-off in-app purchase. 素伊OM asks for nothing beyond the download.

素伊OM ships an update every 6 weeks, Pipe Diameter Calculators every 20 months. Both last shipped on November 3, 2026.

## The numbers

| Metric | 素伊OM | Pipe Diameter Calculators |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | **Every 6 weeks** | Every 20 months |
| Size | 63 MB | 59 MB |
| Requires iOS | **15.0** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 17+ | 4+ |
| Developer | [温州合蚨信息科技有限公司](https://appshunter.io/developer/1542294265) | [Ashvin Kevadiya](https://appshunter.io/developer/1756324971) |

## What reviewers say

### 素伊OM

[App page](https://appshunter.io/ios/app/om/id1542963362)

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

**In-app purchases:** none


### Pipe Diameter Calculators

[App page](https://appshunter.io/ios/app/pipe-diameter-calculators/id6743020859)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime | $9.99 | one-time |


## Frequently asked questions

### Is 素伊OM free?

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

### Is Pipe Diameter Calculators free?

Pipe Diameter Calculators is free to download, with in-app purchases available.

### Do 素伊OM or Pipe Diameter Calculators have ads?

素伊OM shows ads; Pipe Diameter Calculators does not.

### Which is updated more often, 素伊OM or Pipe Diameter Calculators?

素伊OM ships an update every 6 weeks, and Pipe Diameter Calculators every 20 months. Most recently, 素伊OM was updated on November 3, 2026 and Pipe Diameter Calculators on November 3, 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.*