# Hydraulic Calculator Engineer vs Rocket Calculator

The clearest difference is in-app purchases: Hydraulic Calculator Engineer at none against Rocket Calculator's 1. Hydraulic Calculator Engineer also leads on device support (3 vs 1) and iOS requirement (15.0 vs 17.0). Rocket Calculator's advantage is update cadence (weekly vs every 22 months). On price and ads there is nothing between them.

Both are free to download. Rocket Calculator sells 1 one-off in-app purchase. Hydraulic Calculator Engineer asks for nothing beyond the download.

Hydraulic Calculator Engineer ships an update every 22 months, Rocket Calculator weekly. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Hydraulic Calculator Engineer | Rocket Calculator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (9 ratings)](https://appshunter.io/ios/app/hydraulic-calculator-engineer/id1664790770/reviews)** | — |
| Number of ratings | **9** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 22 months | **Weekly** |
| Monetization | Free | — |
| Size | 21 MB | 1 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Arsosa Network Inc.](https://appshunter.io/developer/1209042440) | [毅 王](https://appshunter.io/developer/6774631380) |

## What reviewers say

### Hydraulic Calculator Engineer

[App page](https://appshunter.io/ios/app/hydraulic-calculator-engineer/id1664790770)

This app offers a suite of hydraulic calculations for technicians and engineers. It simplifies complex hydraulics by automatically computing results based on user-entered values, eliminating the need for manual formula application.

**Highlights:** Cylinder Calculation, Power Calculation, Pressure Difference, Piston Diameter, Speed Calculation, Lifting Time, Volume Flow

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

**In-app purchases:** none


### Rocket Calculator

[App page](https://appshunter.io/ios/app/rocket-calculator-apogeefield/id6778329350)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ApogeeField Unlock | $4.99 | one-time |


## Frequently asked questions

### Is Hydraulic Calculator Engineer free?

Hydraulic Calculator Engineer is free to download, with no in-app purchases.

### Is Rocket Calculator free?

Rocket Calculator is free to download, with in-app purchases available.

### Do Hydraulic Calculator Engineer or Rocket Calculator have ads?

Neither Hydraulic Calculator Engineer nor Rocket Calculator shows ads.

### Which is updated more often, Hydraulic Calculator Engineer or Rocket Calculator?

Hydraulic Calculator Engineer ships an update every 22 months, and Rocket Calculator weekly. Most recently, Hydraulic Calculator Engineer was updated on November 3, 2026 and Rocket Calculator on October 31, 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.*