Comparison

Master Electrician Ref. Lite vs Electronics Engineer Helper

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Master Electrician Ref. Lite

This electronic pocket reference guide provides essential information for electrical professionals. It offers calculations, code tables, and detailed sections on motors, ampacities, grounding, and more, all accessible on your mobile device.

Highlights
  • Motor and wiring information
  • Ampacity tables
  • Conduit fill and grounding sizes
  • Voltage drop calculations
  • Conduit bending guide
  • Integrated scientific calculator
  • NEC code tables
Features
Read full description

Master Electrician Reference Lite (or MER Lite for short) is your electronic pocket electrician reference guide. MER Lite is for electrical designers, engineers, installers, contractors, facility managers, inspectors, exam candidates, apprentices, electricians, journeymen, architects, and technicians. MER is for people doing residential, industrial, and commercial work. Simply, if you are a Master Sparky or work with electricity in any way, this reference guide is for you! Have you ever lost pages or had damaged pages in your pocket electricians reference? The solution is here: Use MER Lite to keep the most important information easily accessible on your iPhone, iPod Touch, or iPad. MER Lite will even do calculations for you; something your old pocket reference book can't do. MER Lite is divided into the following sections: * Motors and Wiring - Standard motor and motor starter sizes, tables of full-load currents, locked-rotor information, overload units, OCPD, nameplate information, synchronous motor speeds, three-phase STAR and DELTA diagrams, three-wire start-stop diagram, motor frame dimensions, and motor enclosure types. * Ampacities - Ampacities in raceway, cable, earth, and free air, and derating tables. * Conduit Fill table * Grounding Sizes - Equipment grounding conductor (EGC) and grounding electrode conductor (GEC). * Voltage Drop calculations * Conduit Bending - Includes the guide "The Master Bender Way" on how to bend conduit. See the Master Bender app or MasterBender.com website for more information. * Standard Tool List * Safety - Safety manual and first aid. Most pages contain a general scientific calculator. It is expression based: Just enter an expression and evaluate it. It understands trig and power functions, can convert between radians and degrees, and has built-in basic constants like pi and e. MER includes key NEC tables from the National Electrical Code (NEC) 2011. Visit our website at MasterSparky.com for more information. If you like MER Lite, you will love the full MER. It contains much more information. The full MER are available in versions covering the NEC 2011, 2014, and 2017 code years.

About

Electronics Engineer Helper

This app provides a comprehensive suite of calculators and reference tools for electronics enthusiasts and professionals. It includes features for component identification, circuit calculations, and electrical property analysis, aiding in both study and practical work.

Highlights
  • Datasheet search
  • Resistor color code calculator
  • Electronic schematic symbols
  • Pinouts guide
  • Ohm's law calculator
  • AWG converter
  • Unit converter
Features
Read full description

Digital toolbox for electronics engineers and electricians. Calculators and references for beginners and professionals — for work, study, DIY, and repair. Used by over 100,000 users. Completely ad-free. Included tools: • Datasheet search • Equivalent parts search (cross reference for transistors, diodes and ICs) • Resistor color and digit marking (4, 5 and 6 band color code; 2 symbols, 3/4 digit and EIA-96 code SMD resistors code) • Electronic schematic symbols (IEC 60617, IEEE 315 and GOST standards) • Pinouts of connectors and interfaces (USB, HDMI, DisplayPort, DVI, VGA, Thunderbolt, Apple Lightning and 30-pin, SATA, PCI Express and M.2, Ethernet RJ45 with PoE, RJ11/RJ14/RJ25, RS-232/422/485, IEEE 1394 FireWire, ATX, computer fans, SD card, audio jack, RCA, MIDI, XLR, PS/2, D-sub, SMEMA) • Pinouts of boards and microcontrollers (Raspberry Pi and Pico, Arduino, ESP32, ESP8266, STM32 Nucleo, Teensy, Orange Pi, RADXA Rock Pi, LubanCat, Flipper Zero, ATmega and ATtiny) • Ohm's law calculator • AWG converter (wire diameter, cross-section area, resistance and maximum current) • Resistor for LED • Voltage divider • Wheatstone bridge (output voltage or unknown resistance, current and power of every arm) • Capacitor code • Capacitor markings • Capacitor ESR tables • Frequency response curve calculation of passive filters (RC, RL, RLC, LC) • Inductor color code • Air-core coil calculator (inductance or number of turns of a single-layer solenoid) • Ideal transformer (winding turns, voltages and currents) • Linear current regulator • SMD packages list • Reactance • PCB trace resistance • Active, apparent and reactive power • RMS converter (peak, RMS and peak-to-peak values for seven waveform shapes) • 555 waveform generator • Operational amplifiers • RLC circuit • Number conversion • Unit converter • Cable voltage drop • Battery life (runtime of a battery pack, with discharge curve) • NTC thermistor resistance • Logic gates • RC circuit • Decibels calculator • 25-pair cable color code • Fuse color marking Additionally, by purchasing the PRO version of the app, you will get access to additional tools: • SMD components marking codes • Diodes color code (Pro Electron, JEDEC and JIS-C-7012 standards) • Linear voltage regulator • Resistor value to color or SMD code marking converter • Voltage rectifier • Series or parallel electrical components' connection calculator • Diode voltage drop • Minimum PCB trace width • Analog to digital conversion • Attenuators • 4-20 mA signal converter • Thermocouple calculator • Resistance thermometer • Buck switching voltage regulator • Wire resistance • Zener diode regulator (Zener diode and series resistor selection from a catalogue of 438 parts) • Load cell (bridge output voltage to weight, force, pressure or torque) • BJT voltage divider biasing • Transformer turns per volt (from core area, flux density and frequency) • Junction temperature (with or without a heatsink, power derating curve) • Solar string dimensioning (minimum voltage and current ratings for a PV array) • Solar cable and fuse selection (NEC and IEC rules) • 555 astable generator with variable duty cycle • NTC thermistor in a voltage divider and with an ADC input Privacy Policy: https://www.eehelper.app/ios/privacy/ Terms of Use: https://www.eehelper.app/ios/terms/

Screenshots

Master Electrician Ref. Lite4 screens
Electronics Engineer Helper4 screens

Verdict

The call

Master Electrician Ref. Lite and Electronics Engineer Helper both sit at 4.7 stars, but that hides the real split: 98% of Electronics Engineer Helper's written reviews are positive against 50% of Master Electrician Ref. Lite's. Electronics Engineer Helper also leads on update cadence (monthly vs every 4 months). Master Electrician Ref. Lite's advantage is in-app purchases (none vs 2) and ratings volume (2.5K vs 436). On price, rating, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Electronics Engineer Helper sells 2 in-app purchases, starting at $4.89 per year. Master Electrician Ref. Lite asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.7 for Master Electrician Ref. Lite against 4.8 for Electronics Engineer Helper. That said, the two scores are not equally well evidenced: Master Electrician Ref. Lite has 2.5K ratings behind it against 436, so its average is the more settled of the two. Written reviews are what separate them: 50% of Master Electrician Ref. Lite's written reviews are positive against 98% of Electronics Engineer Helper's.

UpkeepUpdate frequency

Master Electrician Ref. Lite ships an update every 4 months, Electronics Engineer Helper monthly. The most recent releases landed on October 9, 2026 and October 11, 2026 respectively.

Scorecard6 real differences · 4 level
Master Electrician Ref. Lite versus Electronics Engineer Helper: the parameters behind the verdict, then further details
ParameterMaster Electrician Ref. LiteElectronics Engineer Helper
PriceFreeFree
Rating4.7 (2.5K ratings)4.8 (436 ratings) — better
Positive reviews50.0% of reviews97.7% of reviews — better
Number of ratings2.5K — better436
Update frequencyEvery 4 monthsMonthly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhone, iPad, iPodiPhone, iPad, Mac
Requires iOS11.4 — better17.0
Further details — not scored
Size46 MB92 MB
Age rating12+12+
DeveloperPawEng, LLCRostyslav Dovhaliuk

Customer experience

Master Electrician Ref. Lite

All ratings2,509 ratings
Positive92.6%
Neutral4.6%
Negative2.8%
Written reviews6 reviews
Positive50.0%
Neutral16.7%
Negative33.3%

Electronics Engineer Helper

All ratings436 ratings
Positive97.5%
Neutral1.6%
Negative0.9%
Written reviews172 reviews
Positive97.7%
Neutral0.6%
Negative1.7%

Bugs and requests

Master Electrician Ref. Lite

Not enough reviews yet to summarise bugs or requests.

Electronics Engineer Helper

Reported bugs

2 issues
  • Incorrect resistor color code display for some values
  • In-app purchase option not working for some users

Requested features

5 requests
  • Add more circuit schematics and examples
  • Include ASCII code to decimal, hex, and octal conversion
  • Expand the pinout section with more details
  • Add active filter (RC, RL, RLC, LC) calculators
  • Include digital to analog converter, transistor, and transformer calculators

In-app purchases

None

Master Electrician Ref. Lite

No in-app purchases

2 purchases

Electronics Engineer Helper

Subscriptions1
  • 1 Year Subscription1 Month trial$4.891 Year
One-time1
  • Lifetime PRO Version$12.49

Questions

Is Master Electrician Ref. Lite free?
Master Electrician Ref. Lite is free to download, with no in-app purchases.
Is Electronics Engineer Helper free?
Electronics Engineer Helper is free to download, with in-app purchases available.
Which has better reviews, Master Electrician Ref. Lite or Electronics Engineer Helper?
Electronics Engineer Helper is rated higher. Master Electrician Ref. Lite averages 4.7 out of 5 from 2.5K ratings, while Electronics Engineer Helper averages 4.8 from 436 ratings.
Do Master Electrician Ref. Lite or Electronics Engineer Helper have ads?
Neither Master Electrician Ref. Lite nor Electronics Engineer Helper shows ads.
Which is updated more often, Master Electrician Ref. Lite or Electronics Engineer Helper?
Master Electrician Ref. Lite ships an update every 4 months, and Electronics Engineer Helper monthly. Most recently, Master Electrician Ref. Lite was updated on October 9, 2026 and Electronics Engineer Helper on October 11, 2026.

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