Formula library
1,250 formulas spanning circuits, fields, communications, and more — organized by topic and searchable when a number won't come to mind.
ELECTRONICS ENGINEERING · ECE BOARD REVIEW
Wire your way
through the boards.
Electron packs a full review library, a practice bank, and a timed exam simulator into one Android app — so every formula you need is one tap away, on or off the grid.
1,250
Formulas
12,000
Practice problems
12,000
Worked solutions
60 min
Exam Mode clock
MODULES ON THE BOARD
Five components, one circuit.
Every part of the review process gets its own dedicated module — swap between them the way you'd swap parts on a breadboard.
Practice bank
12,000 problems paired with 12,000 full solutions, so you can check your work step by step instead of just seeing a final answer.
Exam Mode
A one-hour timed simulator that mirrors board-exam pressure, so test day is the second time you've felt this clock — not the first.
AI Assistant
Stuck on a derivation or a wording? Ask the built-in assistant to walk through the concept instead of hunting through old notes.
Flashcards
Spaced formula flashcards that charge up your recall the way a capacitor holds a charge — a quick top-up between review sessions.
Privacy by default
No data collected, nothing shared with third parties. The app runs on ads to stay free — never on your information.
FROM THE LIBRARY
1,250 formulas. A few samples.
CircuitsV = IROhm's Law
Resonancefr = 1 / 2π√(LC)Resonant Frequency
PowerP = VI cos θReal Power (AC)
FieldsF = kq₁q₂ / r²Coulomb's Law
CommsC = B log₂(1+S/N)Shannon Capacity
SignalsXC = 1 / 2πfCCapacitive Reactance
Every formula links out to matching practice problems, so theory and drilling stay one tap apart.
INSIDE THE APP
A closer look at the board.
ABOUT ELECTRON
Built by a reviewee, for reviewees.
Electron started as a personal formula sheet and grew into a full review companion for the Electronics Engineering board exam. It's built and maintained by Jens Lennard Refugido Cruz, an independent developer working under the name IntelliJens.
The app is free to use and supported by ads — no account, no paywall, and no personal data collected or shared with third parties.
- Category — Education
- Content rating — Rated for 3+
- Data safety — No data collected · Nothing shared with third parties
- Developer identity — PWD Developer
Developer
Jens Lennard Refugido Cruz
IntelliJens · Philippines
PWD Developer
GOOD TO KNOW
Frequently asked questions
Is Electron free to use?
Yes. The full formula library, practice bank, and Exam Mode are free. The app shows ads to stay that way.
What is Exam Mode?
A timed, one-hour simulation of board-exam conditions, drawn from the practice bank, so you can rehearse pacing before the real thing.
Does the AI Assistant need an internet connection?
The AI Assistant sends your question out to answer it, so it needs a connection. The formula library and flashcards work without one.
What data does Electron collect?
None. Electron's Play Store listing declares no data collected and nothing shared with third parties. Full detail is in the Privacy Policy.
I found a bug or have a feature request — who do I contact?
Email blackpieces14@gmail.com with details, or reach out through the developer's site.
Ready to close the loop?
Install Electron and carry the formula library, practice bank, and Exam Mode in your pocket.
Get it on Google Play