# iEngineer vs Virtual Flange Slide Rule

The clearest difference is in-app purchases: Virtual Flange Slide Rule at none against iEngineer's 1. Virtual Flange Slide Rule also leads on rating (5.0 vs 4.5) and review sentiment (100% vs 86%). iEngineer's advantage is ratings volume (201 vs 13). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. iEngineer sells 1 one-off in-app purchase. Virtual Flange Slide Rule asks for nothing beyond the download.

Virtual Flange Slide Rule holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: iEngineer has 201 ratings behind it against 13, so its average is the more settled of the two. Written reviews point the same way: 86% of iEngineer's written reviews are positive against 100% of Virtual Flange Slide Rule's.

iEngineer ships an update every 5 months, Virtual Flange Slide Rule every 4 months. Both last shipped on November 1, 2026.

## The numbers

| Metric | iEngineer | Virtual Flange Slide Rule |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.5 (201 ratings)](https://appshunter.io/ios/app/iengineer/id369825047/reviews) | **[5.0 (13 ratings)](https://appshunter.io/ios/app/virtual-flange-slide-rule/id546358145/reviews)** |
| Number of ratings | **201** | 13 |
| Positive reviews | 85.5% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 4 months** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 12 MB | 3 MB |
| Requires iOS | 26.0 | **15.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Perfectly Simple Apps LLC](https://appshunter.io/developer/357604157) | [American Certified Equipment, Inc.](https://appshunter.io/developer/546358148) |

## 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


### Virtual Flange Slide Rule

[App page](https://appshunter.io/ios/app/virtual-flange-slide-rule/id546358145)

Access essential measurements and dimensional data for API 6A integral flanges. This tool provides quick access to critical specifications for engineering and industrial applications.

**Highlights:** API 6A integral flange data, Relevant measurements, Dimensional data access, Engineering specifications

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is iEngineer free?

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

### Is Virtual Flange Slide Rule free?

Virtual Flange Slide Rule is free to download, with no in-app purchases.

### Which has better reviews, iEngineer or Virtual Flange Slide Rule?

Virtual Flange Slide Rule is rated higher. iEngineer averages 4.5 out of 5 from 201 ratings, while Virtual Flange Slide Rule averages 5.0 from 13 ratings.

### Do iEngineer or Virtual Flange Slide Rule have ads?

Neither iEngineer nor Virtual Flange Slide Rule shows ads.

### Which is updated more often, iEngineer or Virtual Flange Slide Rule?

iEngineer ships an update every 5 months, and Virtual Flange Slide Rule every 4 months. Most recently, iEngineer was updated on November 1, 2026 and Virtual Flange Slide Rule on November 1, 2026.

---

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