# Mechanical Engineer vs ISO Fits

The clearest difference is review sentiment: ISO Fits at 95% against Mechanical Engineer's 30%. ISO Fits also leads on iOS requirement (15.6 vs 17.6). Mechanical Engineer's advantage is rating (4.4 vs 4.2) and update cadence (every 2 months vs every 5 months). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Mechanical Engineer sells 3 in-app purchases, starting at $0.99 per month and ISO Fits sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Mechanical Engineer holds the better App Store score, 4.4 against 4.2. Both are backed by a comparable volume of ratings — 8 and 6 respectively. Written reviews complicate that: 30% of Mechanical Engineer's written reviews are positive against 95% of ISO Fits's, so the app with the better star average is not the one people write more warmly about.

Mechanical Engineer ships an update every 2 months, ISO Fits every 5 months. The most recent releases landed on October 31, 2026 and November 2, 2026 respectively.

## The numbers

| Metric | Mechanical Engineer | ISO Fits |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.4 (8 ratings)](https://appshunter.io/ios/app/mechanical-engineer/id327055140/reviews)** | [4.2 (6 ratings)](https://appshunter.io/ios/app/iso-fits/id396863755/reviews) |
| Number of ratings | **8** | 6 |
| Positive reviews | 29.6% of reviews | **94.6% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 5 months |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 5 MB | 66 MB |
| Requires iOS | 17.6 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Historycentral.com](https://appshunter.io/developer/1744330560) | [Trelleborg Sealing Solutions](https://appshunter.io/developer/396863758) |

## What reviewers say

### Mechanical Engineer

[App page](https://appshunter.io/ios/app/mechanical-engineer/id327055140)

This app provides over 300 essential mechanical engineering formulas across various domains. It allows users to calculate, save, compare, and share results, aiding in project optimization and decision-making. Users can access a limited number of calculations for free, with a subscription unlocking full functionality.

**Highlights:** Over 300 mechanical engineering formulas, Covers diverse engineering domains, Save and compare formula results, Share calculation outcomes, Intuitive and practical interface, Regular updates based on user input

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $0.99 | per month |
| Pro Quarterly | $0.99 | per 3 months |
| Pro Yearly | $2.99 | per year |


### ISO Fits

[App page](https://appshunter.io/ios/app/iso-fits/id396863755)

Calculate ISO fits and tolerances for shafts and bores. Supports metric and inch units, displays detailed fit definitions, and includes visual charts and educational videos.

**Highlights:** ISO fits calculation, Tolerance class display, Metric/inch unit switching, Tolerance charts, Updated YouTube videos

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Version with complete ISO286 Standard | $1.99 | one-time |


## Frequently asked questions

### Is Mechanical Engineer free?

Mechanical Engineer is free to download, with in-app purchases available.

### Is ISO Fits free?

ISO Fits is free to download, with in-app purchases available.

### Which has better reviews, Mechanical Engineer or ISO Fits?

Mechanical Engineer is rated higher. Mechanical Engineer averages 4.4 out of 5 from 8 ratings, while ISO Fits averages 4.2 from 6 ratings.

### Do Mechanical Engineer or ISO Fits have ads?

Neither Mechanical Engineer nor ISO Fits shows ads.

### Which is updated more often, Mechanical Engineer or ISO Fits?

Mechanical Engineer ships an update every 2 months, and ISO Fits every 5 months. Most recently, Mechanical Engineer was updated on October 31, 2026 and ISO Fits on November 2, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*