# c vs Engineer's Unit Converter

The clearest difference is in-app purchases: c at none against Engineer's Unit Converter's 1. c also leads on ads (none vs shown) and iOS requirement (15.0 vs 18.0). On price, update cadence and device support there is nothing between them.

Both are free to download. Engineer's Unit Converter sells 1 one-off in-app purchase. c asks for nothing beyond the download.

c ships an update every 3 weeks, Engineer's Unit Converter monthly. The most recent releases landed on November 5, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | c | Engineer's Unit Converter |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | **Every 3 weeks** | Monthly |
| Size | 31 MB | 7 MB |
| Requires iOS | **15.0** | 18.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [Wuhan Longhe Intelligent Technology Co., Ltd.](https://appshunter.io/developer/1848853099) | [Jose Gerardo Palma Duran](https://appshunter.io/developer/1873843788) |

## What reviewers say

### c

[App page](https://appshunter.io/ios/app/c-carlink/id6754557918)

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

**In-app purchases:** none


### Engineer's Unit Converter

[App page](https://appshunter.io/ios/app/engineers-unit-converter/id6758744042)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $0.99 | one-time |


## Frequently asked questions

### Is c free?

c is free to download, with no in-app purchases.

### Is Engineer's Unit Converter free?

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

### Do c or Engineer's Unit Converter have ads?

Engineer's Unit Converter shows ads; c does not.

### Which is updated more often, c or Engineer's Unit Converter?

c ships an update every 3 weeks, and Engineer's Unit Converter monthly. Most recently, c was updated on November 5, 2026 and Engineer's Unit Converter on October 31, 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.*