Comparison

Mohr's Circle vs Polygon

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

Head to head
About

Mohr's Circle

This application assists users in performing Mohr's Circle calculations and verifying their diagrams. It offers solutions for 2D plane stress, calculates various stress values, and generates graphical representations of stress states. Users can also share results and store multiple stress states.

Highlights
  • 2D Plane Stress Mohr's Circle Solutions
  • Max, Min, and Shear Stress Calculations
  • Principal Stress Plane Angle
  • Mohr's Circle Diagram
  • Stress State Rotation Views
  • Shareable Results
  • Unit Conversion (English/Metric)
Features
Currently charting
Read full description

Do you need to perform a Mohr's Circle calculation? Would you like to make sure you Mohr's Circle diagram is correct? With the power of your iOS device and this app, you can do this quickly and easily. (5 Stars) "Perfect…Great tool, great app!" -The fever, the focus Mohr's Circle Calculates: ● 2D Plane Stress Mohr's Circle Solutions ● Max Stress ● Min Stress ● Max Shear Stress ● Average Stress ● Principal Stress Plane Angle ● Max Shear Stress Plane Angle ● The normal stress at an arbitrary angle ● The tangential stress at an arbitrary angle ● The shear stress at an arbitrary angle Mohr's Circle Graphs 4 Views Including: ● Mohr's Circle Diagram ● Stress State Rotated to the Principal Stress Plane ● Stress State Rotated to the Max Shear Stress Plane ● Stress State Rotated to an arbitrary angle Mohr's Circle Features: ● Universal App (Designed for both the iPhone and iPad) ● Share your results via a printout or email ● View the equations used to calculate the results ● Store as many stress states as you want for future reference Units Included! Independently set input and output units both English and Metric. Check out our other engineering apps by searching the App Store for: • Pressure Vessel Pro • Moments of Inertia • Stress Concentrations Pro • Stress Intensity Factors Pro or search J.R.Hobbs to see them all. AppStore.com/JRHobbs

About

Polygon

Calculate complex properties of any polygonal figure, including centroids, moments of inertia, and perimeter. Simply input vertex coordinates for instant results, saving significant time on tedious calculations.

Highlights
  • Polygon Centroids
  • Moments of Inertia (Ix, Iy, Ixy)
  • Polar Moment of Inertia
  • Radius of Gyration
  • Principal Moments of Inertia
  • Area and Perimeter
  • Side Lengths
  • Hollow Sections
Features
Read full description

Polygon will allow you to calculate complex and tedious calculations related to any polygonal figure, whether concave or convex, regular or irregular, in a simple and instantaneous way: - Polygon Centroids - Moments of Inertia Ix, Iy, Ixy - Polar Moment of Inertia - Radius of gyration - Principal Moments of Inertia (Iu, Iv and their respective angles) - Area and Perimeter of the polygon - Length of each side of the polygon - Even incorporate hollow sections - Rotate the axes to a custom angle - Define new custom axes at any point - and much more You just have to enter the coordinates of the vertices of your polygon and press the button and it will immediately calculate all the previous properties, saving valuable time. Subscription Terms: Payment will be charged to Itunes Account at confirmation of purchase. Subscription automatically renews unless auto-renew is turnerd off at least 24-hours before the end of the current period. Account will be charged for renewal within 24-hour prior to the end of the current period, and identify the cost of the renewal. Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Setting after purchase. No cancellation of the current subscription is allowed during active subscription period. For in-app purchases and subscriptions, see Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Mohr's Circle4 screens
Polygon4 screens

Verdict

The call

The clearest difference is price: Polygon at Free against Mohr's Circle's $5.99. Polygon also leads on update cadence (weekly vs every 15 months). Mohr's Circle's advantage is in-app purchases (none vs 4) and rating (3.3 vs 3.0). On ads 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

Polygon is free to download; Mohr's Circle costs $5.99 up front. Polygon sells 4 in-app purchases, starting at $2.99 per month. Mohr's Circle asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Mohr's Circle holds the better App Store score, 3.3 against 3.0. Both are backed by a comparable volume of ratings — 3 and 1 respectively.

UpkeepUpdate frequency

Mohr's Circle ships an update every 15 months, Polygon weekly. The most recent releases landed on September 16, 2026 and September 20, 2026 respectively.

Scorecard8 real differences · 3 level
Mohr's Circle versus Polygon: the parameters behind the verdict, then further details
ParameterMohr's CirclePolygon
Price$5.99Free — better
Rating3.3 (3 ratings) — better3.0 (1 ratings)
Positive reviews42.9% of reviews—
Number of ratings3 — better1
Update frequencyEvery 15 monthsWeekly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFreemium — better
Best chart rank#191 — better—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS12.0 — better17.0
Further details — not scored
Size8 MB29 MB
Age rating4+4+
DeveloperJ.R.HobbsAdrian Caballero

Customer experience

Mohr's Circle

All ratings3 ratings
Positive66.7%
Neutral0.0%
Negative33.3%
Written reviews7 reviews
Positive42.9%
Neutral28.6%
Negative28.6%

Polygon

All ratings1 ratings
Positive0.0%
Neutral100.0%
Negative0.0%

In-app purchases

None

Mohr's Circle

No in-app purchases

4 purchases

Polygon

Subscriptions3
  • Pro Access$2.991 Month
  • Pro Access$4.996 Months
  • Pro Access$6.991 Year
One-time1
  • Pro Access$9.99

Questions

Is Mohr's Circle free?
Mohr's Circle costs $5.99, with no in-app purchases.
Is Polygon free?
Polygon is free to download, with in-app purchases available.
Which has better reviews, Mohr's Circle or Polygon?
Mohr's Circle is rated higher. Mohr's Circle averages 3.3 out of 5 from 3 ratings, while Polygon averages 3.0 from 1 ratings.
Do Mohr's Circle or Polygon have ads?
Neither Mohr's Circle nor Polygon shows ads.
Which is updated more often, Mohr's Circle or Polygon?
Mohr's Circle ships an update every 15 months, and Polygon weekly. Most recently, Mohr's Circle was updated on September 16, 2026 and Polygon on September 20, 2026.

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