# Hydraulic Engineer vs 3DX Catalogs

The clearest difference is price: 3DX Catalogs at Free against Hydraulic Engineer's $4.99. 3DX Catalogs also leads on in-app purchases (none vs 1) and iOS requirement (10.0 vs 18.6). On ads and device support there is nothing between them.

3DX Catalogs is free to download; Hydraulic Engineer costs $4.99 up front. Hydraulic Engineer sells 1 one-off in-app purchase. 3DX Catalogs asks for nothing beyond the download.

## The numbers

| Metric | Hydraulic Engineer | 3DX Catalogs |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | **[4.0 (1 ratings)](https://appshunter.io/ios/app/hydraulic-engineer/id410465591/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 25.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 6 months | — |
| Monetization | Paid | — |
| Size | 19 MB | 43 MB |
| Requires iOS | 18.6 | **10.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Historycentral.com](https://appshunter.io/developer/1744330560) | [Endeavor Business Media LLC](https://appshunter.io/developer/1497183143) |

## What reviewers say

### Hydraulic Engineer

[App page](https://appshunter.io/ios/app/hydraulic-engineer/id410465591)

This comprehensive calculator app offers over 1,000 hydraulic engineering formulas across 13 categories. It includes temperature conversions, reference tables, and the ability to save and share calculations. Works offline and supports both US Customary and SI Metric units.

**Highlights:** Over 1,000 hydraulic formulas, 13 specialized calculator categories, Temperature scale converters, Professional reference tables, Save and share calculations, Works offline, US Customary and SI Metric units

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Hydraulic Pro | $3.99 | one-time |


### 3DX Catalogs

[App page](https://appshunter.io/ios/app/3dx-catalogs/id1499155018)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Hydraulic Engineer free?

Hydraulic Engineer costs $4.99, and also offers in-app purchases.

### Is 3DX Catalogs free?

3DX Catalogs is free to download, with no in-app purchases.

### Do Hydraulic Engineer or 3DX Catalogs have ads?

Neither Hydraulic Engineer nor 3DX Catalogs 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.*