# SI To USCS unit Conversion vs Captain Code NEC Code Changes

The clearest difference is review sentiment: SI To USCS unit Conversion at 100% against Captain Code NEC Code Changes's 33%. SI To USCS unit Conversion also leads on rating (5.0 vs 3.4) and ads (none vs shown). Captain Code NEC Code Changes's advantage is update cadence (every 4 months vs every 10 months) and ratings volume (5 vs 1). On price, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

SI To USCS unit Conversion holds the better App Store score, 5.0 against 3.4. That said, the two scores are not equally well evidenced: Captain Code NEC Code Changes has 5 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 100% of SI To USCS unit Conversion's written reviews are positive against 33% of Captain Code NEC Code Changes's.

SI To USCS unit Conversion ships an update every 10 months, Captain Code NEC Code Changes every 4 months. Both last shipped on June 10, 2026.

## The numbers

| Metric | SI To USCS unit Conversion | Captain Code NEC Code Changes |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/si-to-uscs-unit-conversion/id502598595/reviews)** | [3.4 (5 ratings)](https://appshunter.io/ios/app/captain-code-nec-code-changes/id1516284674/reviews) |
| Number of ratings | 1 | **5** |
| Positive reviews | **100.0% of reviews** | 33.3% of reviews |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 10 months | **Every 4 months** |
| Monetization | **Free** | Ad-supported |
| Size | 1 MB | 16 MB |
| Requires iOS | 14.3 | **12.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Muralidhar Shenoy](https://appshunter.io/developer/460148822) | [Leviton Manufacturing Co. Inc.](https://appshunter.io/developer/877607790) |

## What reviewers say

### SI To USCS unit Conversion

[App page](https://appshunter.io/ios/app/si-to-uscs-unit-conversion/id502598595)

This app facilitates quick unit conversions between SI and USCS/Imperial systems for engineering applications. It covers 18 major categories, including mass, length, volume, and thermodynamics properties. Users can input data and generate conversion tables.

**Highlights:** SI to USCS/Imperial unit conversion, 18 major unit categories, Engineering and applied science focus, Data input and conversion, Conversion table generation, Gas flow rate conversion

**Features:** macOS Compatibility

**In-app purchases:** none


### Captain Code NEC Code Changes

[App page](https://appshunter.io/ios/app/captain-code-nec-code-changes/id1516284674)

This app provides electrical professionals with up-to-date National Electrical Code information. It offers searchable access to code changes, expert analysis, and manufacturer insights, complete with illustrations to aid comprehension.

**Highlights:** Searchable by market vertical, product, or article number, Direct NEC text extraction, Expert analysis from IAEI, Manufacturer input for code intent, Includes photos and illustrations, Tracks code changes from 2014-2023

**In-app purchases:** none


## Frequently asked questions

### Is SI To USCS unit Conversion free?

SI To USCS unit Conversion is free to download, with no in-app purchases.

### Is Captain Code NEC Code Changes free?

Captain Code NEC Code Changes is free to download, with no in-app purchases.

### Which has better reviews, SI To USCS unit Conversion or Captain Code NEC Code Changes?

SI To USCS unit Conversion is rated higher. SI To USCS unit Conversion averages 5.0 out of 5 from 1 ratings, while Captain Code NEC Code Changes averages 3.4 from 5 ratings.

### Do SI To USCS unit Conversion or Captain Code NEC Code Changes have ads?

Captain Code NEC Code Changes shows ads; SI To USCS unit Conversion does not.

### Which is updated more often, SI To USCS unit Conversion or Captain Code NEC Code Changes?

SI To USCS unit Conversion ships an update every 10 months, and Captain Code NEC Code Changes every 4 months. Most recently, SI To USCS unit Conversion was updated on June 10, 2026 and Captain Code NEC Code Changes on June 10, 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.*