Comparison

Hydraulic vs O

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

Head to head
About

Hydraulic

Perform essential hydraulic calculations for cylinders, pumps, and fluid lines. Solve for forces, speeds, torque, power, and pressure drop. Supports metric and imperial units, with advanced features unlocked via in-app purchase.

Highlights
  • Cylinder force and speed calculations
  • Pump displacement, flow, and pressure calculations
  • Hydraulic line fluid velocity and pressure drop
  • Orifice flow and pressure calculations
  • Speed, torque, and power calculations
  • Metric and imperial unit support
  • Copy results to clipboard
Features
Read full description

The Hydraulic Calculator includes many basic hydraulic calculations. Cylinder calculations can be done to solve for extension / retraction forces or speeds. Pump calculations can also be done by entering combinations of displacement, oil flow and pressure to determine values for speed, torque and power. Both mechanical and volumetric efficiencies can be used in these calculations. Hydraulic line calculations can also be done for fluid velocity, cross sectional area, Reynolds number and pressure drop. The free version is limited to 1” or 25mm line diameters. Orifice calculations can also be made using three parameters: Oil Flow, Orifice Diameter and Pressure Drop. Enter any two values and have the third calculated. Speed - Torque - Power page: Enter any two values have the third calculated. Unit conversions built into the page. Calculations can be done in either metric or imperial units. Basic unit conversions are also available. With the in-app purchase, all features from the Hydraulic Calculator will become active: Cylinder characteristics can be entered in a number of different ways. Enter hydraulic flow, cylinder velocity, or stroke time and calculate the other two. User can also enter Hydraulic pressure, extend force or retract force and have the other two calculated. One application for this is to measure the stroke time of a cylinder. By entering this with the bore diameter and stroke length, the system flow is calculated. Full motor & pump calculation page. The motor & pump calculator are flexible tools in which the user can enter any three known values to have the remaining values calculated. Values include: displacement, oil flow, pressure, rotational speed, torque, and motor power. Both mechanical and volumetric efficiency values are used. Results can be copied to the clipboard in a text format for use in e-mails, messages, or other documentation.

About

O

Features
Read full description

Transform Your O-Ring Measurement with AI Precision! Say goodbye to guesswork and inaccurate measurements. Our cutting-edge app uses advanced AI technology to determine the exact size of your O-rings with just a snap of a photo. Whether you’re a professional in the automotive, plumbing, or manufacturing industries, or a DIY enthusiast, our app is designed to make your life easier and your work more precise. Key Features: - Instant Measurements: Simply take a photo of your O-ring, and let our AI do the rest. Get precise measurements in seconds without any hassle. - High Accuracy: Our advanced AI algorithms ensure that you get the exact dimensions of your O-rings every time, eliminating the risk of errors. - User-Friendly Interface: The app is designed with a clean and intuitive interface, making it easy for anyone to use, regardless of technical expertise. - Versatile Application: Ideal for various industries, including automotive, plumbing, manufacturing, and more. Whether you need to measure O-rings for professional projects or home repairs, this app is your perfect companion. - Step-by-Step Guidance: Follow the simple instructions to ensure you capture the perfect photo for accurate measurements every time. Why Choose Our App? Our app leverages the latest in AI technology to bring you unparalleled accuracy and convenience. No more fumbling with manual tools or second-guessing your measurements. Just snap, measure, and get back to what you do best.

Screenshots

Hydraulic4 screens
O3 screens

Verdict

The call

The clearest difference is in-app purchases: O at none against Hydraulic's 2. Hydraulic's advantage is update cadence (every 6 weeks vs every 13 months) and device support (3 vs 1). On price, ads and iOS requirement 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

Both are free to download. Hydraulic sells 2 one-off in-app purchases. O asks for nothing beyond the download.

UpkeepUpdate frequency

Hydraulic ships an update every 6 weeks, O every 13 months. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

Scorecard3 real differences · 7 level
Hydraulic versus O: the parameters behind the verdict, then further details
ParameterHydraulicO
PriceFreeFree
Rating4.1 (17 ratings) — better—
Positive reviews50.0% of reviews—
Number of ratings17 — better—
Update frequencyEvery 6 weeks — betterEvery 13 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone
Requires iOS15.1 — better16.2
Further details — not scored
Size24 MB5 MB
Age rating4+4+
DeveloperZanthic Automation Inc.AppBakkers BV

In-app purchases

2 purchases

Hydraulic

One-time2
  • Full Version$7.99
  • Pro Version$7.99
None

O

No in-app purchases

Questions

Is Hydraulic free?
Hydraulic is free to download, with in-app purchases available.
Is O free?
O is free to download, with no in-app purchases.
Do Hydraulic or O have ads?
Neither Hydraulic nor O shows ads.
Which is updated more often, Hydraulic or O?
Hydraulic ships an update every 6 weeks, and O every 13 months. Most recently, Hydraulic was updated on November 1, 2026 and O on November 3, 2026.

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