Comparison

O vs Mechanical Engg. Calculator

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

Head to head
About

O

This app provides a comprehensive offline tool for selecting standard rubber seal sizes, including O-Rings, X-Rings, and Back-Up Rings. It offers dimension searches, housing calculations for various sealing applications, and supports multiple international standards in both metric and imperial units.

Highlights
  • Offline standard rubber seal size selection
  • Search for O-Ring, X-Ring, and Back-Up Ring sizes
  • O-Ring housing calculations for sealing applications
  • Supports multiple international standards (AS568, METRIC, JIS, etc.)
  • Metric and Imperial unit support
  • Substitutable O-Ring size suggestions
Features
Read full description

GMORS O-Ring Master is the completed tool for standard rubber seal sizes. When you use this APP, you don't need to have internet and catalog. Except O-Ring sizes, it also includes the search functions of X-Ring and Back-Up Ring. Otherwise, you can also use O-Ring Housing to choose suitable O-Ring in your application. Main functions are as follows: Dimension Search:O-Ring, X-Ring and Back-Up Ring. - MM and Inch are both available. - Full standard O-Ring series: AS568, BS 4518, GB/T 3452.1, JIS B2401 P, JIS B2401 G, JIS B2401 S, JIS B2401 V, SMS 1586 and METRIC. - Collocated Back-Up for AS-568 O-Ring. - Substitutable O-Ring sizes within tolerance are available. O-Ring Housing: Piston Sealing、Rod Sealing and Face Sealing. - MM and Inch are both available. - Support calculation for both Static and Dynamic sealing applications (Face sealing is with static calculation only). - Up to 7 O-Ring standards ( AS568, METRIC, JIS B2401 P/G/S/V, JASO F404, GB/T 3452.1, BS 4518 and SMS 1586) for most of size requirement of different groove design.

About

Mechanical Engg. Calculator

This app provides a comprehensive collection of ~250 formulas across 16 categories for mechanical engineering, physics, and mathematics. Users can easily perform calculations by selecting a formula and inputting variables.

Highlights
  • ~250 formulas
  • 16 categories
  • Mathematics, physics, mechanical engineering
  • User-friendly calculation input
  • Customizable for convenience
Features
Read full description

An excellent tool for mechanical engineers or students at university and college, the Trelleborg Sealing Solutions Mechanical Engineering Formula Calculator offers ~250 formulas in 16 categories, with more being added in upcoming updates. Categories include the fields of mathematics, physics, and mechanical engineering. To perform calculations, all a user needs to do is choose a formula and enter the required variables. The app will then calculate the equation and display the result. For faster and convenient calculations the Formula Calculator can be customized on an individual level. The following categories are available: • Actuator • Algebra • Bearing • Fluid Power • Gravitation • Kinematics • Kinetic Energy • Kinetic theory of gases • Laws of motion • Oscillations • Properties of solid and liquid • Rotational motion • Thermodynamics • Trigonometry • Waves and sound • Work energy power

Screenshots

O4 screens
Mechanical Engg. Calculator4 screens

Verdict

The call

The clearest difference is review sentiment: O at 100% against Mechanical Engg. Calculator's 25%. O also leads on rating (5.0 vs 3.7). Mechanical Engg. Calculator's advantage is device support (3 vs 1) and ratings volume (3 vs 1). On price, update cadence, ads and in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

O holds the better App Store score, 5.0 against 3.7. Both are backed by a comparable volume of ratings — 1 and 3 respectively. Written reviews point the same way: 100% of O's written reviews are positive against 25% of Mechanical Engg. Calculator's.

UpkeepUpdate frequency

O ships an update every 11 months, Mechanical Engg. Calculator every 21 months. Both last shipped on November 2, 2026.

Scorecard5 real differences · 5 level
O versus Mechanical Engg. Calculator: the parameters behind the verdict, then further details
ParameterOMechanical Engg. Calculator
PriceFreeFree
Rating5.0 (1 ratings) — better3.7 (3 ratings)
Positive reviews100.0% of reviews — better25.0% of reviews
Number of ratings13 — better
Update frequencyEvery 11 months — betterEvery 21 months
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhoneiPhone, iPad, iPod — better
Requires iOS16.013.0 — better
Further details — not scored
Size47 MB24 MB
Age rating4+4+
DeveloperGE MAO RUBBER INDUSTRIAL CO., LTD.Trelleborg Sealing Solutions

Customer experience

O

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Mechanical Engg. Calculator

All ratings3 ratings
Positive66.7%
Neutral0.0%
Negative33.3%
Written reviews4 reviews
Positive25.0%
Neutral0.0%
Negative75.0%

In-app purchases

None

O

No in-app purchases

None

Mechanical Engg. Calculator

No in-app purchases

Questions

Is O free?
O is free to download, with no in-app purchases.
Is Mechanical Engg. Calculator free?
Mechanical Engg. Calculator is free to download, with no in-app purchases.
Which has better reviews, O or Mechanical Engg. Calculator?
O is rated higher. O averages 5.0 out of 5 from 1 ratings, while Mechanical Engg. Calculator averages 3.7 from 3 ratings.
Do O or Mechanical Engg. Calculator have ads?
Neither O nor Mechanical Engg. Calculator shows ads.
Which is updated more often, O or Mechanical Engg. Calculator?
O ships an update every 11 months, and Mechanical Engg. Calculator every 21 months. Most recently, O was updated on November 2, 2026 and Mechanical Engg. Calculator on November 2, 2026.

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