# Hydraulic Engineer vs NWS Mobile

The clearest difference is price: NWS Mobile at Free against Hydraulic Engineer's $4.99. NWS Mobile also leads on review sentiment (60% vs 25%) and in-app purchases (none vs 1). On ads there is nothing between them.

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

NWS Mobile holds the better App Store score, 4.4 against 4.0. That said, the two scores are not equally well evidenced: NWS Mobile has 96 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 25% of Hydraulic Engineer's written reviews are positive against 60% of NWS Mobile's.

Hydraulic Engineer ships an update every 6 months, NWS Mobile every 2 weeks. The most recent releases landed on November 1, 2026 and November 9, 2026 respectively.

## The numbers

| Metric | Hydraulic Engineer | NWS Mobile |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | [4.0 (1 ratings)](https://appshunter.io/ios/app/hydraulic-engineer/id410465591/reviews) | **[4.4 (96 ratings)](https://appshunter.io/ios/app/nws-mobile/id6756777435/reviews)** |
| Number of ratings | 1 | **96** |
| Positive reviews | 25.0% of reviews | **60.5% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 6 months | **Every 2 weeks** |
| Monetization | Paid | **Free** |
| Size | 19 MB | 93 MB |
| Requires iOS | 18.6 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Historycentral.com](https://appshunter.io/developer/1744330560) | [New World Solutions Pty Ltd](https://appshunter.io/developer/1509390111) |

## 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 |


### NWS Mobile

[App page](https://appshunter.io/ios/app/nws-mobile/id6756777435)

This app helps Jehovah's Witnesses organize congregation activities, including meeting parts, public talks, and duties. It also features territory management and data sharing with the NW Publisher app.

**Highlights:** Congregation overview and information, Christian Life & Ministry meeting scheduling, Public Talk assignments, Duty scheduling, Territory management, Data sharing with NW Publisher app

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Hydraulic Engineer free?

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

### Is NWS Mobile free?

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

### Which has better reviews, Hydraulic Engineer or NWS Mobile?

NWS Mobile is rated higher. Hydraulic Engineer averages 4.0 out of 5 from 1 ratings, while NWS Mobile averages 4.4 from 96 ratings.

### Do Hydraulic Engineer or NWS Mobile have ads?

Neither Hydraulic Engineer nor NWS Mobile shows ads.

### Which is updated more often, Hydraulic Engineer or NWS Mobile?

Hydraulic Engineer ships an update every 6 months, and NWS Mobile every 2 weeks. Most recently, Hydraulic Engineer was updated on November 1, 2026 and NWS Mobile on November 9, 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.*