Comparison

CSiUnits 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

CSiUnits

This application provides a comprehensive tool for converting units across various scientific disciplines and everyday needs. It offers over 70 conversion options, catering to professionals, students, and anyone requiring precise unit transformations.

Highlights
  • Multiple one-time conversion lists
  • Conversions for lifestyle and science
  • Over 70 conversion options
  • Numeric value input
  • Converted values to all possible units
Read full description

CSiUnits is an app that helps in conversion of units. Target Users: • Individuals who need simple to complex unit conversion • Engineers, consultants and various professionals • Students and faculty Key Features: • Multiple one time conversion list • Conversions for various lifestyle needs and branches of science • More than 70 conversions to choose from Key Input: • Numeric value to be converted • Selected primary unit Key Output: • Converted values to all possible units

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

CSiUnits4 screens
Mechanical Engineering Toolkit4 screens

Verdict

The call

The clearest difference is in-app purchases: CSiUnits at none against Mechanical Engineering Toolkit's 1. CSiUnits also leads on ads (none vs shown) and iOS requirement (9.0 vs 15.0). Mechanical Engineering Toolkit's advantage is update cadence (weekly vs monthly) and ratings volume (64 vs 4). On price, rating, review sentiment 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

Both are free to download. Mechanical Engineering Toolkit sells 1 one-off in-app purchase. CSiUnits asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.8 for CSiUnits against 4.8 for Mechanical Engineering Toolkit. That said, the two scores are not equally well evidenced: Mechanical Engineering Toolkit has 64 ratings behind it against 4, so its average is the more settled of the two. Written reviews are what separate them: 50% of CSiUnits's written reviews are positive against 57% of Mechanical Engineering Toolkit's.

UpkeepUpdate frequency

CSiUnits ships an update monthly, Mechanical Engineering Toolkit weekly. The most recent releases landed on September 17, 2026 and October 10, 2026 respectively.

Scorecard6 real differences · 4 level
CSiUnits versus Mechanical Engineering Toolkit: the parameters behind the verdict, then further details
ParameterCSiUnitsMechanical Engineering Toolkit
PriceFreeFree
Rating4.8 (4 ratings)4.8 (64 ratings)
Positive reviews50.0% of reviews57.1% of reviews — better
Number of ratings464 — better
Update frequencyMonthlyWeekly — better
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree — betterAd-supported
DevicesiPhone, iPad, iPodiPhone, iPad, iPod, Mac — better
Requires iOS9.0 — better15.0
Further details — not scored
Size13 MB40 MB
Age rating4+4+
DeveloperComputers and Structures, Inc.APPS BAY LIMITED

Customer experience

CSiUnits

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive50.0%
Neutral50.0%
Negative0.0%

Mechanical Engineering Toolkit

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

In-app purchases

None

CSiUnits

No in-app purchases

1 purchases

Mechanical Engineering Toolkit

One-time1
  • Remove Ads$2.99

Questions

Is CSiUnits free?
CSiUnits 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, CSiUnits or Mechanical Engineering Toolkit?
CSiUnits and Mechanical Engineering Toolkit are both rated 4.8 out of 5 on the App Store, from 4 and 64 ratings respectively.
Do CSiUnits or Mechanical Engineering Toolkit have ads?
Mechanical Engineering Toolkit shows ads; CSiUnits does not.
Which is updated more often, CSiUnits or Mechanical Engineering Toolkit?
CSiUnits ships an update monthly, and Mechanical Engineering Toolkit weekly. Most recently, CSiUnits was updated on September 17, 2026 and Mechanical Engineering Toolkit on October 10, 2026.

Other comparisons