Cryptarithmetic vs Logic Gates

Cryptarithms — crack the code of numbers What if the digits in mathematical equations were replaced with letters? Your task is to figure out which digit is hidden behind each letter. Sounds simple? Give it a try. How it works You are given an equation like “COT + COT = DOMA”. Each letter represents a unique digit from 0 to 9. Find all the matches so that the math works out. One letter — one digit. No randomness, just logic. Five game modes Classic — solve at your own pace with no time limits Timed — race against the clock for adrenaline lovers Zen — no scores or rankings, just pure enjoyment of the process Daily puzzle — one unique challenge every 24 hours Tournament — five puzzles in a row, total score, a true test Four difficulty levels From simple two-digit equations for beginners to multi-layered challenges with 10 unique variables for true mathematical detectives. Progression system Earn points and experience for every solution. Rise from Beginner to Immortal through 10 mastery levels. Unlock 25 achievements — from your first solution to marathon win streaks. Hints without pressure Stuck? Spend points on a hint — one letter will be revealed. In Zen mode, hints are always free. Don’t want to spend points — watch a short ad. Thoughtful details — Dark and light themes that follow system settings — Daily reminders (customizable) — Detailed statistics: best streaks, average time, breakdown by difficulty — Supports addition, subtraction, and multiplication — Endless generation of unique puzzles Cryptarithms have existed since the early 20th century and remain one of the most elegant forms of mathematical puzzles. Now in your pocket. Train your mind. Every day.

Wire switches to gates, gates to the bulb, and watch real logic come alive. Logic Gates teaches you how computers actually think — not with videos or flashcards, but by letting you build every circuit yourself. Each puzzle gives you a truth table and a handful of gates. Drag wires, flip switches, test every row, and light the bulb. When it clicks, it stays clicked — because you built it. LEARN ALL SEVEN GATES Start with a single AND gate and work up to multi-stage circuits that use everything: AND, OR, NOT, XOR, XNOR, NAND, and NOR. Six chapters, 34 puzzles, completely free. BUILT FOR UNDERSTANDING, NOT MEMORISING • A guided first lesson gets you wiring in under a minute • Interactive gate cards introduce each new gate hands-on • Three-tier hints when you're stuck — always free, never paywalled • Earn up to three stars per puzzle with mastery challenges: shorter chains, cleaner wiring, the right final gate A WORKBENCH, NOT A WORKSHEET • Flip switches and watch signals flow through your circuit live • Test any truth-table row instantly • Full undo and redo, with your work-in-progress saved automatically • Calm, synthesized soundscape — no jingles, no pressure, no timers COMING SOON: LOGIC IN THE REAL WORLD A free update will add an optional pack of ten applied puzzles built from real systems: burglar alarms, safety interlocks, fail-safe design, two-person rules, voting circuits, comparators, and parity checks. See the same gates you learned running the real world. FAIR BY DESIGN • No ads. No subscriptions. No consumables. • The full seven-gate curriculum is free forever • Everything in this release is free — the optional pack arrives in a future update • Everything runs on your device, fully offline — your data never leaves it MADE FOR EVERYONE • Full VoiceOver support — every wire can be placed by tapping, no dragging required • iPhone and iPad, including Split View and Stage Manager • No account, no sign-in, no tracking Whether you're a student meeting Boolean logic for the first time, a programmer who wants to know what's underneath the code, or simply someone who loves puzzles that leave you smarter — grab a wire and see for yourself why AND, OR, and NOT run everything.