Comparison

Converter vs Mechanical Engineering Toolkit

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

Head to head
About

Converter

This app offers a comprehensive unit and hardness conversion tool with an easy-to-use interface. It includes currency conversion with updated exchange rates, over 300 engineering and scientific units, and a specialized hardness converter. Additional features like timezone conversion, pace calculation, and a standard calculator enhance its utility.

Highlights
  • Currency converter with live exchange rates
  • Over 300 engineering and scientific units
  • Specialized hardness converter
  • Timezone conversion
  • Running pace calculator
  • Integrated standard calculator
  • Conversion history log
Features
Read full description

Trelleborg’s “Unit and Hardness Converter” converts a comprehensive list of units (incl. currencies) in an easy way. In addition, the app has a set of other useful features on board, like timezone conversion, percentage calculations, a running pace calculator and more What our users say: “Have been using it forever, never tried other converter as this one does the job perfectly” - Lazareth_fr “Fabulous resource, but also a functional masterpiece!” -Otto. “This is needed by all engineers. So simple and easy to use” -JLa03.   FEATURES • Easy-to-use interface • Currency converter with in-app exchange rate update functionality • Over 300 engineering and scientific conversion units in 32 categories • Hardness converter with 16 conversion tables based on ASTM E140-07 and ISO-18265 for quick conversion between different scales • Video library: features the extensive Trelleborg Sealing Solutions YouTube library • Toggle between units • Switch between dark and white theme • Conversion history log • Create favorite lists • Standard calculator integrated with unit converter DIMENSIONS • Area • Currency • Current • Data • Density • Distance • Dynamic Viscosity • Energy • Force • Frequency • Kinematic Viscosity • Moment of inertia • Power • Prefixes • Pressure • Speed • Strength • Temperature • Time • Torque • Volume • Weight • Fuel Consumption • Glucose • Vacuum • Numbers • Illumination • Radioactivity • Radiation (absorbed) • Angles • Volume Flow Rate • Calorie • Metric Prefixes • Typography • Electric Charge OTHER MISCELLANEOUS CATEGORIES • Timezone conversion • Clothing sizes / Shoe sizes • International power plugs • Running pace calculator • Percentage calculator • Pace • Hex, Binary, Decimal • BMI (metric/inch) HARDNESS SCALES INCLUDED • Rockwell (HRC, HRA, HRD, HRF, HRG, HRE, HR-15-N, HR-30N, HR-45-N, HR45-T, HR-15T, HR-30T, HR45-T) • Brinell (HBW, HBS) • Vickers (HV, • Knoop (HK) The app is available in English, German and Chinese languages. Download now or contact us with any questions.

About

Mechanical Engineering Toolkit

This utility app provides a comprehensive collection of engineering equations and formulas for students and professionals. Easily perform calculations by selecting a formula and inputting variables, with detailed instructions and reference material included.

Highlights
  • Engineering equations and formulas
  • Mechanics of Material calculations
  • Theory of Elasticity formulas
  • Composite Material properties
  • Reference material
  • Variable input for calculations
Features
Read full description

Mechanical Engineering Toolkit is a professional engineering calculator for students, researchers, and practicing engineers. Choose a formula, enter your variables, and get instant results — with calculation steps, formulas, diagrams, and unit conversions shown along the way. Switch between SI and Imperial units anytime, save favorites, and find the right tool fast with recommendations by major. Save your inputs as named projects, and export any result as text, image, CSV or PDF. Categories and tools: Mechanics of Material • Moments of inertia of plane areas • Force-displacement relation of a bar • Torsion formula and angle of twist • Flexure formula of a beam • Transverse shear stress • Deflections and slopes of cantilever and simple beams • Plane stress transformation and Mohr's circle • Principal stresses and planes • Spherical shell and thin-walled pressure vessel stresses • Buckling load of a column • Thermal deformation and stress • Combined loading • Bolted / riveted joints • Fatigue safety factor • Shaft power and torque Statics • Centroid of an area • Resultant of a force system • Beam reactions • 2D truss analysis Machine Design • Helical compression springs • Spur gear geometry and stresses • Shaft fatigue design (DE-Goodman) • Bearing L10 life • Belt and chain drives • Bolt preload / torque-tension • Fillet weld strength • Press / shrink-fit interference • Shaft critical speed (Dunkerley) • Beam natural frequency (five end conditions) • Torsional natural frequency (one or two rotors) Fluids & Thermal • Reynolds number and flow regime • Pipe pressure drop (Darcy-Weisbach with Colebrook) • Pump and fan power • Composite wall conduction • Fin efficiency • Heat exchanger sizing by LMTD Theory of Elasticity • Constitutive relation of linear elastic material • Stress/strain of linear elastic material Composite Material • Lamina and laminate stress/strain • Lamina engineering constants • Laminate plane and 3D properties • Rule of mixtures • Failure criteria (Tsai-Hill, Tsai-Wu) Reference Tables • Drill & tap chart (metric and imperial thread series) • ISO 286 fits & tolerances • Standard sections (AISC W, IPE, HEB) • Unit converter No account required. Works offline. Available in English, Chinese, German, French, and Japanese.

Screenshots

Converter4 screens
Mechanical Engineering Toolkit4 screens

Verdict

The call

Converter and Mechanical Engineering Toolkit both sit at 4.9 stars, but that hides the real split: 96% of Converter's written reviews are positive against 57% of Mechanical Engineering Toolkit's. Converter also leads on in-app purchases (none vs 1) and ads (none vs shown). Mechanical Engineering Toolkit's advantage is update cadence (weekly vs every 2 months). On price, rating, device support 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. Mechanical Engineering Toolkit sells 1 one-off in-app purchase. Converter asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.9 for Converter against 4.8 for Mechanical Engineering Toolkit. That said, the two scores are not equally well evidenced: Converter has 897 ratings behind it against 64, so its average is the more settled of the two. Written reviews are what separate them: 96% of Converter's written reviews are positive against 57% of Mechanical Engineering Toolkit's.

UpkeepUpdate frequency

Converter ships an update every 2 months, Mechanical Engineering Toolkit weekly. The most recent releases landed on October 11, 2026 and October 10, 2026 respectively.

Scorecard6 real differences · 4 level
Converter versus Mechanical Engineering Toolkit: the parameters behind the verdict, then further details
ParameterConverterMechanical Engineering Toolkit
PriceFreeFree
Rating4.9 (897 ratings) — better4.8 (64 ratings)
Positive reviews96.0% of reviews — better57.1% of reviews
Number of ratings897 — better64
Update frequencyEvery 2 monthsWeekly — better
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree — betterAd-supported
DevicesiPhone, iPad, iPodiPhone, iPad, iPod, Mac — better
Requires iOS15.615.0 — better
Further details — not scored
Size37 MB40 MB
Age rating12+4+
DeveloperTrelleborg Sealing SolutionsAPPS BAY LIMITED

Customer experience

Converter

All ratings897 ratings
Positive98.1%
Neutral1.3%
Negative0.6%
Written reviews225 reviews
Positive96.0%
Neutral2.2%
Negative1.8%

Mechanical Engineering Toolkit

All ratings64 ratings
Positive95.3%
Neutral1.6%
Negative3.1%
Written reviews7 reviews
Positive57.1%
Neutral14.3%
Negative28.6%

Bugs and requests

Converter

Reported bugs

2 issues
  • Occasional crashes on startup for non-English/German users
  • Conversion from meters to feet does not show inches

Requested features

3 requests
  • Add fuel efficiency conversions
  • Allow users to set favorite conversions as default
  • Improve currency conversion rate updates

Mechanical Engineering Toolkit

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Converter

No in-app purchases

1 purchases

Mechanical Engineering Toolkit

One-time1
  • Remove Ads$2.99

Questions

Is Converter free?
Converter is free to download, with no in-app purchases.
Is Mechanical Engineering Toolkit free?
Mechanical Engineering Toolkit is free to download, with in-app purchases available.
Which has better reviews, Converter or Mechanical Engineering Toolkit?
Converter is rated higher. Converter averages 4.9 out of 5 from 897 ratings, while Mechanical Engineering Toolkit averages 4.8 from 64 ratings.
Do Converter or Mechanical Engineering Toolkit have ads?
Mechanical Engineering Toolkit shows ads; Converter does not.
Which is updated more often, Converter or Mechanical Engineering Toolkit?
Converter ships an update every 2 months, and Mechanical Engineering Toolkit weekly. Most recently, Converter was updated on October 11, 2026 and Mechanical Engineering Toolkit on October 10, 2026.

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