Comparison

PrepFE vs Commercial Electrical Designer

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

Head to head
About

PrepFE

Prepare for your FE exam with practice problems and flashcards. Learn by doing with expert-curated content, track your progress, and identify areas for improvement. Study anytime, anywhere with this mobile resource.

Highlights
  • Practice FE exam questions
  • Interactive practice exams
  • Hundreds of practice questions
  • Detailed step-by-step explanations
  • Flashcards for key concepts
  • Progress tracking and weakness analysis
  • Updated content for new specifications
Features
Read full description

Don't spend time relearning topics from scratch and using poor resources. Jump right into practice problems and learn by doing! Supplement your learning with flash cards to learn the FE Reference Handbook and be familiar with your discipline's concepts. Take your exam practice on the go and learn with our curated content by engineering experts. Study whenever and wherever it’s convenient with PrepFE™. No need to carry around books and study guides. All you need is your phone and determination. Start your Professional Engineer journey and download the PrepFE - Electrical & Computer app. Install the free version today and jump start your studying! We have provided a limited free version of the app that you can try before deciding to upgrade. This version includes a limited set of practice questions, flash cards, and basic progress metrics. *Practice FE exam questions* *Interactive Practice Exams* *Hundreds of Practice Questions* *Detailed & Step-by-Step Explanations* *Reinforce learning with Flash Cards* *Breakdown of strengths and weaknesses* *Updated for 2020* We have up to date content for the new category specifications: • Mathematics • Probability and Statistics • Ethics and Professional Practice • Engineering Economics • Properties of Electrical Materials • Circuit Analysis (DC and AC Steady State) • Linear Systems • Signal Processing • Electronics • Power Systems • Electromagnetics • Control Systems • Communications • Computer Networks • Digital Systems • Computer Systems • Software Engineering

About

Commercial Electrical Designer

Features
Read full description

This app is a visual reference and calculation tool for electrical engineers, designers, electricians, and students working on commercial building projects. Built around a real-world commercial strip mall, this app puts professional electrical illustrations, NEC code look-up, interactive calculators, step-by-step design calculation guides, a project checklist, and an electrical glossary in one place — offline, on iPhone and iPad. BROWSE — ILLUSTRATED DRAWINGS 23 professional illustrations in 8 design categories: Floor Plans & Key Plans — dimensioned tenant layouts and color-coded key plans Electrical Plans — device plans with lighting, receptacles, switches, and panels Wiring Layouts — branch circuit home runs and wiring path diagrams Electrical Symbols & Legend — full device symbol reference Panelboard Schedules — 200A, 208Y/120V, 3-phase schedules for Shops A, B, C, and the Building 2 main distribution panel Panelboard Load Worksheets — conductor sizing tables with OCPD ratings and wire sizes per circuit Feeder Load Calculation Worksheets — NEC Article 220 calculations for each tenant and the building main Conductor & Conduit Sizing Steps — step-by-step sizing sheets for phase, neutral, and grounding conductors Pinch to zoom up to 6× on any illustration. Swipe between images in the same category. Save any illustration to Favorites for fast retrieval. NEC REFERENCE Searchable, expandable code cards for the articles most relevant to commercial design: Article 210 (Branch Circuits), 215 (Feeders), 220 (Calculations), 230 (Services), 240 (Overcurrent Protection), 250 (Grounding and Bonding), 310 (Conductors), and 408 (Panelboards). CALCULATORS Ten interactive calculators covering the full commercial design workflow: Branch Circuit Load, Feeder Load, Voltage Drop, Wire Sizing, Conduit Fill, Panel Load Balance, Demand Factor, Short Circuit Current, Power Factor Correction, and Service Size. DESIGN CALCULATIONS Seven step-by-step calculation modules with NEC references, formulas, and worked examples: Branch Circuit Load Worksheet, Feeder Load Calculation, Phase Conductor Sizing, Neutral Conductor Sizing, Equipment Grounding Conductor, Conduit Fill & Trade Size, and Panelboard Load & Phase Balancing — including a full Building 2 Panel L1 worked example. PROJECT CHECKLIST (NEW IN 1.1) A phase-by-phase checklist covering the full commercial electrical project workflow — Pre-Design, Load Calculations, Conductor Sizing, Panelboard Design, Drawing Set, Permit & Approval, and Final Inspection. Each item includes the applicable NEC reference. Progress is tracked automatically and saved between sessions. ELECTRICAL GLOSSARY (NEW IN 1.1) 55+ NEC and electrical engineering terms with plain-language definitions and code references — alphabetically indexed and fully searchable. Covers key terms including Ampacity, Branch Circuit, Continuous Load, Demand Factor, EGC, Feeder, FLA, GFCI, AFCI, OCPD, Power Factor, Service Entrance, Unit Load, Voltage Drop, and more. FOR iPHONE AND iPAD Fully responsive layout adapts to any screen size and orientation. All content is available offline — no subscription or account required. Ideal for electrical engineering students, practicing engineers, electrical designers, contractors, and inspection professionals working with NEC-based commercial electrical systems.

Screenshots

PrepFE4 screens
Commercial Electrical Designer4 screens

Verdict

The call

The clearest difference is price: PrepFE at Free against Commercial Electrical Designer's $2.99. PrepFE also leads on iOS requirement (13.0 vs 17.0). Commercial Electrical Designer's advantage is in-app purchases (none vs 6) and update cadence (monthly vs every 36 months). On 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

PrepFE is free to download; Commercial Electrical Designer costs $2.99 up front. PrepFE sells 6 one-off in-app purchases. Commercial Electrical Designer asks for nothing beyond the download.

UpkeepUpdate frequency

PrepFE ships an update every 36 months, Commercial Electrical Designer monthly. The most recent releases landed on October 21, 2026 and October 19, 2026 respectively.

Scorecard4 real differences · 6 level
PrepFE versus Commercial Electrical Designer: the parameters behind the verdict, then further details
ParameterPrepFECommercial Electrical Designer
PriceFree — better$2.99
Rating2.6 (8 ratings) — better—
Positive reviews0.0% of reviews—
Number of ratings8 — better—
Update frequencyEvery 36 monthsMonthly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better17.0
Further details — not scored
Size288 MB42 MB
Age rating4+4+
DeveloperPrepFE, Inc.Yuhsiu Lai

In-app purchases

6 purchases

PrepFE

One-time6
  • 1 Month Access Renewal$47.99
  • 1 Month Access$59.99
  • 3 Months Access Renewal$61.99
Show 3 more
  • 6 Months Access Renewal$75.99
  • 3 Months Access$79.99
  • 6 Months Access$99.99
None

Commercial Electrical Designer

No in-app purchases

Questions

Is PrepFE free?
PrepFE is free to download, with in-app purchases available.
Is Commercial Electrical Designer free?
Commercial Electrical Designer costs $2.99, with no in-app purchases.
Do PrepFE or Commercial Electrical Designer have ads?
Neither PrepFE nor Commercial Electrical Designer shows ads.
Which is updated more often, PrepFE or Commercial Electrical Designer?
PrepFE ships an update every 36 months, and Commercial Electrical Designer monthly. Most recently, PrepFE was updated on October 21, 2026 and Commercial Electrical Designer on October 19, 2026.

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