# iEngineer vs Unit Converter

iEngineer and Unit Converter both sit at 4.5 stars, but that hides the real split: 86% of iEngineer's written reviews are positive against 34% of Unit Converter's. Unit Converter's advantage is ratings volume (16K vs 201) and iOS requirement (17.6 vs 26.0). On price, rating, update cadence and ads there is nothing between them.

Both are free to download. iEngineer sells 1 one-off in-app purchase and Unit Converter sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 4.5 for iEngineer against 4.6 for Unit Converter. That said, the two scores are not equally well evidenced: Unit Converter has 16K ratings behind it against 201, so its average is the more settled of the two. Written reviews are what separate them: 86% of iEngineer's written reviews are positive against 34% of Unit Converter's.

iEngineer ships an update every 5 months, Unit Converter every 3 months. The most recent releases landed on November 1, 2026 and November 6, 2026 respectively.

## The numbers

| Metric | iEngineer | Unit Converter |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.5 (201 ratings)](https://appshunter.io/ios/app/iengineer/id369825047/reviews) | **[4.6 (16K ratings)](https://appshunter.io/ios/app/unit-converter-pro-units-app/id1139120257/reviews)** |
| Number of ratings | 201 | **16K** |
| Positive reviews | **85.5% of reviews** | 33.9% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 months** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 12 MB | 10 MB |
| Requires iOS | 26.0 | **17.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Perfectly Simple Apps LLC](https://appshunter.io/developer/357604157) | [Tue Nguyen Minh](https://appshunter.io/developer/434811167) |

## What reviewers say

### iEngineer

[App page](https://appshunter.io/ios/app/iengineer/id369825047)

Access a vast database of screw and bolt information, including dimensions, material grades, and strength properties for both US and metric fasteners. Features a comprehensive drill chart, unit conversion, and customizable material displays.

**Highlights:** Extensive US screw database, Metric screw database (in-app purchase), Detailed dimensions and material grades, Strength, torque, and clamp force data, Head markings and 3D head models, Comprehensive drill chart, Unit conversion and data export

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Metric Screws | $1.99 | one-time |

**What reviewers like**

- 🚀 Easy to navigate
- 👍 Comprehensive information
- 🔧 Useful for everyday work
- ⚙️ Essential for engineers and machinists
- 💡 Saves time compared to physical references

**What reviewers complain about**

- 🐛 Occasional errors in torque and tensile strength data
- 💰 Metric information requires paid upgrade
- 🔍 Missing some thread types like NPT and BSPP

**Reported bugs**

- Metric portion not working for some users
- Camera access request for no apparent reason

**Requested features**

- Add tap drill chart
- Include clearance hole fits
- Improve UI for larger displays
- Add French language support


### Unit Converter

[App page](https://appshunter.io/ios/app/unit-converter-pro-units-app/id1139120257)

This app offers a powerful and user-friendly unit converter with 16 categories, including currency, length, and temperature. It allows for custom unit lists and provides live exchange rate updates for 148 currencies. Unlock all features with a one-time in-app purchase.

**Highlights:** 16 conversion categories, Custom unit lists, Live currency exchange rates, 148 world currencies supported, User-friendly interface

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Features | $2.99 | one-time |

**What reviewers like**

- 👍 Easy to use
- 🚀 Simple design
- 👍 Covers many units
- 👍 User-friendly layout
- 👍 Accurate conversions

**What reviewers complain about**

- 🔒 Limited functionality without paying
- 🔒 Most common units locked behind paywall
- 🐛 Restore purchase not working
- 🐛 Unreliable app support
- 🔒 Conversion categories locked

**Reported bugs**

- Conversion results not always accurate
- App freezes or crashes on some devices
- Purchased features not always accessible

**Requested features**

- Add calculator functionality
- Improve currency conversion
- Provide more unit categories
- Allow creating custom formulas


## Frequently asked questions

### Is iEngineer free?

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

### Is Unit Converter free?

Unit Converter is free to download, with in-app purchases available.

### Which has better reviews, iEngineer or Unit Converter?

Unit Converter is rated higher. iEngineer averages 4.5 out of 5 from 201 ratings, while Unit Converter averages 4.6 from 16K ratings.

### Do iEngineer or Unit Converter have ads?

Neither iEngineer nor Unit Converter shows ads.

### Which is updated more often, iEngineer or Unit Converter?

iEngineer ships an update every 5 months, and Unit Converter every 3 months. Most recently, iEngineer was updated on November 1, 2026 and Unit Converter on November 6, 2026.

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