Comparison

Hydraulic Engineer vs Pressure Unit Converter

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Hydraulic Engineer

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
Read full description

HYDRAULIC ENGINEER is the most comprehensive hydraulic engineering calculator available on the App Store, featuring over 1,000 formulas across 13 specialized calculator categories, 8 temperature scale converters, and 8 professional reference tables. CALCULATOR CATEGORIES - Actuator Formulas — cylinder force, stroke, speed, and rod calculations - Fluid Power — pressure, flow, horsepower, and torque calculations - Pump Laws — affinity laws for speed, flow, pressure, and power - Vehicle Drive — drive speed, tractive effort, gradeability, and drawbar pull - Hydraulic Tubing — wall thickness, burst pressure, and working pressure - Cylinder Calculations — extend/retract speed, rod end area, and cycle times - Thermal Hydraulics — heat generation, reservoir cooling, heat exchangers, and energy to heat fluid - Oil Velocity & Pressure Loss — pipe velocity, pressure drop per foot, and total system losses - Pipe Flow — Reynolds number, Darcy-Weisbach head loss, laminar friction, and orifice flow - Accumulator Sizing — discharge volume, precharge pressure, adiabatic and isothermal gas volumes - Reservoir Sizing — open/closed circuit sizing, cylinder-based sizing, and oil weight calculations - AC/DC Electrical — Ohm's law, power, resistance, inductance, and motor selection - Area Formulas — 60 geometric area calculations for every common shape 700+ CONVERSION FORMULAS Pressure, horsepower, BTU, flow rates, linear measure, square measure, cubic measure, liquid measure, weights, watts, power, HVAC, metric, sand-to-volume, and fraction conversions. 8 TEMPERATURE SCALES Convert between Celsius, Fahrenheit, Kelvin, Rankine, Reaumur, Newton, Delisle, and Romer — 56 conversion formulas covering every combination. 8 PROFESSIONAL REFERENCE TABLES - Pipe Schedule (Schedule 40 & 80) - ISO Viscosity Grades - Recommended Flow Velocities - Hydraulic Hose Sizing (SAE) - JIC Thread Sizes - Pipe Roughness Values - O-Ring Sizes (AS568) - Wire Rope Working Load Limits KEY FEATURES - Save and share any calculation result - Share reference tables - Calculation history - Favorites for quick access to your most-used formulas - Switch between US Customary and SI Metric units - Dual-unit display shows both US and metric values simultaneously - Dark mode optimized interface - Works offline — no internet connection required PREMIUM UPGRADE Unlock sharing, advanced calculator sections, and unlimited history with a one-time lifetime purchase — no subscriptions. HYDRAULIC ENGINEER is designed for working hydraulic engineers, technicians, maintenance professionals, and engineering students. If there are formulas or reference tables you'd like to see added, just use the built-in feedback feature to let us know.

About

Pressure Unit Converter

Easily convert pressure measurements between various units with customizable rounding options for both decimal and fractional results. Save and email your conversion history for convenient record-keeping.

Highlights
  • Multiple pressure unit support
  • Decimal and fractional result display
  • Customizable rounding for decimals
  • Customizable fraction rounding
  • Conversion history
  • Email results and history
  • Portrait and landscape support
Features
Read full description

A handy app to convert between pressure units. Supported pressure units: • Atmosphere • Millibar • Bar • Pascal • Hectopascal • Kilopascal • Pounds per square inch (PSI) • Pounds per square foot (PSF) • Kilograms per square meter kgf/m² • Inches of mercury (inHg) • Millimeters of mercury (mmHg) • Torr "Flip" button to easily switch between the "from" and "to" units. Supports fractions. Results are shown in the decimal and fractional forms. App's Settings: - Rounding to the specified number of decimal places: for decimal numbers, you can select the number of decimal places you want to display. By default, the app displays 2 decimal places. To round results to the nearest whole number, select 0 decimal places. - For fractions, you can select rounding to the nearest 1/2, 1/4, 1/8, 1/16, 1/32, 1/64, 1/128, 1/256. By default, the app rounds fractions to the nearest 1/32. If you do not need to round fractions, just select "-". Sends results and history via email. Conversion history. Supports both portrait and landscape orientation.

Screenshots

Hydraulic Engineer4 screens
Pressure Unit Converter4 screens

Verdict

The call

The clearest difference is rating: Pressure Unit Converter at 5.0 against Hydraulic Engineer's 4.0. Pressure Unit Converter also leads on review sentiment (67% vs 25%) and in-app purchases (none vs 1). On ratings volume, ads, monetization model and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Hydraulic Engineer costs $4.99 and Pressure Unit Converter $3.99 up front. Hydraulic Engineer sells 1 one-off in-app purchase. Pressure Unit Converter asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Pressure Unit Converter holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively. Written reviews point the same way: 25% of Hydraulic Engineer's written reviews are positive against 67% of Pressure Unit Converter's.

UpkeepUpdate frequency

Hydraulic Engineer ships an update every 6 months, Pressure Unit Converter every 2 months. The most recent releases landed on October 30, 2026 and October 24, 2026 respectively.

Scorecard6 real differences · 4 level
Hydraulic Engineer versus Pressure Unit Converter: the parameters behind the verdict, then further details
ParameterHydraulic EngineerPressure Unit Converter
Price$4.99$3.99 — better
Rating4.0 (1 ratings)5.0 (1 ratings) — better
Positive reviews25.0% of reviews66.7% of reviews — better
Number of ratings11
Update frequencyEvery 6 monthsEvery 2 months — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationPaidPaid
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS18.66.0 — better
Further details — not scored
Size19 MB23 MB
Age rating4+4+
DeveloperHistorycentral.comIntemodino Group s.r.o.

Customer experience

Hydraulic Engineer

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews8 reviews
Positive25.0%
Neutral25.0%
Negative50.0%

Pressure Unit Converter

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive66.7%
Neutral0.0%
Negative33.3%

In-app purchases

1 purchases

Hydraulic Engineer

One-time1
  • Hydraulic Pro$3.99
None

Pressure Unit Converter

No in-app purchases

Questions

Is Hydraulic Engineer free?
Hydraulic Engineer costs $4.99, and also offers in-app purchases.
Is Pressure Unit Converter free?
Pressure Unit Converter costs $3.99, with no in-app purchases.
Which has better reviews, Hydraulic Engineer or Pressure Unit Converter?
Pressure Unit Converter is rated higher. Hydraulic Engineer averages 4.0 out of 5 from 1 ratings, while Pressure Unit Converter averages 5.0 from 1 ratings.
Do Hydraulic Engineer or Pressure Unit Converter have ads?
Neither Hydraulic Engineer nor Pressure Unit Converter shows ads.
Which is updated more often, Hydraulic Engineer or Pressure Unit Converter?
Hydraulic Engineer ships an update every 6 months, and Pressure Unit Converter every 2 months. Most recently, Hydraulic Engineer was updated on October 30, 2026 and Pressure Unit Converter on October 24, 2026.

Other comparisons