# 2017 Master Electrician Ref. vs Subs

The clearest difference is price: Subs at Free against 2017 Master Electrician Ref.'s $9.99. Subs also leads on update cadence (every 2 weeks vs every 5 months). 2017 Master Electrician Ref.'s advantage is in-app purchases (none vs 1) and device support (3 vs 1). On ads there is nothing between them.

Subs is free to download; 2017 Master Electrician Ref. costs $9.99 up front. Subs sells 1 one-off in-app purchase. 2017 Master Electrician Ref. asks for nothing beyond the download.

2017 Master Electrician Ref. ships an update every 5 months, Subs every 2 weeks. The most recent releases landed on October 18, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | 2017 Master Electrician Ref. | Subs |
| --- | --- | --- |
| Price | $9.99 | **Free** |
| Rating | **[4.7 (1.3K ratings)](https://appshunter.io/ios/app/2017-master-electrician-ref/id1275949959/reviews)** | — |
| Number of ratings | **1.3K** | — |
| Positive reviews | 66.7% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 2 weeks** |
| Monetization | Paid | — |
| Size | 46 MB | 2 MB |
| Requires iOS | **12.0** | 18.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 12+ | 4+ |
| Developer | [PawEng, LLC](https://appshunter.io/developer/390058606) | [展 陆](https://appshunter.io/developer/1874538134) |

## What reviewers say

### 2017 Master Electrician Ref.

[App page](https://appshunter.io/ios/app/2017-master-electrician-ref/id1275949959)

This digital handbook provides electricians and related professionals with essential electrical formulas, diagrams, and reference tables. It offers calculations, a dictionary of terms, and detailed information on wiring, motors, transformers, and more, all accessible on a mobile device.

**Highlights:** Electrical formulas and calculations, Wiring diagrams for various systems, Motor and transformer specifications, Conductor and ampacity tables, Dictionary of electrician terms, NEMA standards and diagrams, Math and conversion tools

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

**In-app purchases:** none

**What reviewers like**

- 👍 Quick reference
- 🚀 Best app for electrical information
- 🚀 Concise and well-laid out information
- 🚀 Comprehensive electrical references

**What reviewers complain about**

- 🐛 App needs to be updated
- 🐛 Inaccurate information in some areas
- 🐛 Limited functionality compared to expectations
- 🐛 Overlapping table of contents

**Reported bugs**

- Conduit fill information missing for certain types
- Login screen freezes
- Compatibility issues with older devices

**Requested features**

- Update to latest NEC code
- Add calculation tools for conduit fill and voltage drop
- Improve user interface and navigation


### Subs

[App page](https://appshunter.io/ios/app/subs-subscription-manager/id6758752966)

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Upgrade to Pro | $1.99 | one-time |


## Frequently asked questions

### Is 2017 Master Electrician Ref. free?

2017 Master Electrician Ref. costs $9.99, with no in-app purchases.

### Is Subs free?

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

### Do 2017 Master Electrician Ref. or Subs have ads?

Neither 2017 Master Electrician Ref. nor Subs shows ads.

### Which is updated more often, 2017 Master Electrician Ref. or Subs?

2017 Master Electrician Ref. ships an update every 5 months, and Subs every 2 weeks. Most recently, 2017 Master Electrician Ref. was updated on October 18, 2026 and Subs on October 17, 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.*