# OML Directory vs Open Channel Flow Pro

The clearest difference is price: OML Directory at Free against Open Channel Flow Pro's $2.99. OML Directory also leads on iOS requirement (10.0 vs 15.0). On ads, in-app purchases and device support there is nothing between them.

OML Directory is free to download; Open Channel Flow Pro costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

## The numbers

| Metric | OML Directory | Open Channel Flow Pro |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | — | **[1.7 (3 ratings)](https://appshunter.io/ios/app/open-channel-flow-pro/id1576457515/reviews)** |
| Number of ratings | — | **3** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | — | Every 3 months |
| Monetization | — | Paid |
| Size | 25 MB | 2 MB |
| Requires iOS | **10.0** | 15.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 17+ | 4+ |
| Developer | [Empowered Margins](https://appshunter.io/developer/1548442706) | [Alexius Academia](https://appshunter.io/developer/1209840214) |

## What reviewers say

### OML Directory

[App page](https://appshunter.io/ios/app/oml-directory/id1548442704)

**Features:** macOS Compatibility

**In-app purchases:** none


### Open Channel Flow Pro

[App page](https://appshunter.io/ios/app/open-channel-flow-pro/id1576457515)

This hydraulic engineering calculator simplifies complex open channel flow calculations for professionals and students. It provides accurate results for basic parameters, flow characteristics, critical flow analysis, and rating curves.

**Highlights:** Basic Hydraulic Parameters, Flow Characteristics, Critical Flow Analysis, Rating Curves, Wetted Perimeter, Area, Hydraulic Radius, Velocity, Froude Number, Hydraulic Depth

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

**In-app purchases:** none


## Frequently asked questions

### Is OML Directory free?

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

### Is Open Channel Flow Pro free?

Open Channel Flow Pro costs $2.99, with no in-app purchases.

### Do OML Directory or Open Channel Flow Pro have ads?

Neither OML Directory nor Open Channel Flow Pro shows ads.

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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.*