Comparison

Mechanical Engineering Toolkit vs PDF Studio(Pro)

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

Head to head
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.

About

PDF Studio(Pro)

Features
Read full description

Welcome to PDF Studio, the ultimate PDF management app designed to provide a comprehensive and powerful document editing experience. The app is equipped with features that cater to both casual users and professionals, ensuring seamless PDF handling for all your needs. Key Features: Scan: Create PDF documents directly from your device camera by scanning physical documents. Images to PDF: Convert multiple images into a single PDF document with ease. Merge: Combine multiple PDF files into one unified document. Split: Divide a single PDF file into separate documents as needed. Watermark: Add custom watermarks to protect and brand your PDF documents. Annotate: Add notes, comments, and annotations to your PDF files. Create: Build new PDF documents from scratch with full customization options. Edit: Add text and images to existing PDF documents. Sign: Add digital signatures to PDF files for authentication and approval. Page Numbers: Insert page numbers throughout your PDF documents. Lock: Secure your PDF files with password protection. Unlock: Remove password protection from locked PDF files. Page Size: Change the page size of your PDF documents to standard formats. Crop: Crop PDF pages to remove unwanted margins or focus on specific content. Compress: Reduce PDF file size without significant quality loss. Rotate Pages: Rotate PDF pages to correct orientation. Extract Pages: Extract specific pages from PDF documents. Duplicate Pages: Create copies of pages within your PDF. Remove Pages: Delete unwanted pages from PDF documents. Rearrange Pages: Reorder pages in your PDF files. Blank Pages: Insert blank pages into your PDF documents. Flip Pages: Flip PDF pages horizontally or vertically. Page Filter: Apply filters like black and white or grayscale to PDF pages. PDF to MP3: Convert PDF text content to audio files. PDF to Images: Convert PDF pages to image files. PDF to TXT: Extract text content from PDF files. Elevate your PDF management experience with PDF Studio, where every feature is crafted to support your document needs. Whether you're merging reports, signing contracts, or organizing documents, the app is your perfect PDF companion. Developed by Anvaysoft Programmer - Hrishi Suthar Made with love in India

Screenshots

Mechanical Engineering Toolkit4 screens
PDF Studio(Pro)4 screens

Verdict

The call

The clearest difference is price: Mechanical Engineering Toolkit at Free against PDF Studio(Pro)'s $2.99. PDF Studio(Pro)'s advantage is in-app purchases (none vs 1) and ads (none vs shown). On 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

Mechanical Engineering Toolkit is free to download; PDF Studio(Pro) costs $2.99 up front. Mechanical Engineering Toolkit sells 1 one-off in-app purchase. PDF Studio(Pro) asks for nothing beyond the download.

UpkeepUpdate frequency

Mechanical Engineering Toolkit ships an update weekly, PDF Studio(Pro) every 2 days. The most recent releases landed on October 15, 2026 and October 3, 2026 respectively.

Scorecard5 real differences · 5 level
Mechanical Engineering Toolkit versus PDF Studio(Pro): the parameters behind the verdict, then further details
ParameterMechanical Engineering ToolkitPDF Studio(Pro)
PriceFree — better$2.99
Rating4.8 (64 ratings) — better—
Positive reviews57.1% of reviews—
Number of ratings64 — better—
Update frequencyWeeklyEvery 2 days — better
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationAd-supported—
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size43 MB42 MB
Age rating4+4+
DeveloperAPPS BAY LIMITEDHrishi Suthar

In-app purchases

1 purchases

Mechanical Engineering Toolkit

One-time1
  • Remove Ads$2.99
None

PDF Studio(Pro)

No in-app purchases

Questions

Is Mechanical Engineering Toolkit free?
Mechanical Engineering Toolkit is free to download, with in-app purchases available.
Is PDF Studio(Pro) free?
PDF Studio(Pro) costs $2.99, with no in-app purchases.
Do Mechanical Engineering Toolkit or PDF Studio(Pro) have ads?
Mechanical Engineering Toolkit shows ads; PDF Studio(Pro) does not.
Which is updated more often, Mechanical Engineering Toolkit or PDF Studio(Pro)?
Mechanical Engineering Toolkit ships an update weekly, and PDF Studio(Pro) every 2 days. Most recently, Mechanical Engineering Toolkit was updated on October 15, 2026 and PDF Studio(Pro) on October 3, 2026.

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