Signal Deck vs Learn Binary

SignalDeck is the essential training companion for mariners, naval cadets, offshore sailors, and maritime enthusiasts who want to master the International Code of Signals (ICS) flag system — the visual language of the sea. Study the Full ICS Flag Set Browse all 36 ICS flags — the complete 26-letter alphabet (Alpha through Zulu) plus 10 numeral pennants (0 through 9) — presented as beautifully rendered flashcards. Each card shows the flag's name, NATO phonetic pronunciation, and its official maritime meaning. Swipe through at your own pace, filter by letters or numerals, or shuffle the deck to keep every session fresh. Three Drill Modes to Test Your Knowledge Visual ID: A flag appears on screen. Can you name it before time runs out? Tap the correct NATO name from four options and build your streak as the pace intensifies. Flag Bag: The challenge flips — you're given a NATO letter or name and must pick the correct flag from four choices. Perfect for cementing the visual recognition you've built in study mode. Flag IQ: A memory match game with a nautical twist. Flip face-down cards on a grid to pair each flag image with its NATO letter or official ICS meaning. Choose Easy (4×4, letter cards), Medium (4×5, meaning cards), or Hard (6×6, mixed) — and earn your rating from Bridge Apprentice to Master Chief Signalman based on how few mismatches you make. Built for Serious Learners Animated flags rendered with authentic nautical proportions and a sea-breeze waving effect Streak tracking with escalating visual feedback as your streak climbs "Needs Practice" summary after every drill — instantly see which flags to revisit Fleet Readiness Heatmap in your drill log — colour-coded badges show your mastery level for every flag at a glance Drill log that records every session so you can track progress over time Timed pressure in Visual ID and Flag Bag mirrors the urgency of real-world flag communication A Living Reference at Sea and Ashore Whether you're preparing for a maritime exam, brushing up before an offshore passage, training cadets, or simply fascinated by the tradition of visual signaling, SignalDeck gives you a focused, distraction-free environment to drill the flags that matter. Free to Start — Go Premium for Unlimited Access New users get free drill sessions to explore the app. Watch a short ad to unlock another round, or upgrade to Premium for unlimited drills, no ads, and full access to every mode and difficulty tier. The sea doesn't wait. Neither should your training.

Finally understand binary and hex — by doing, not memorising. Learn Binary turns number-base conversion into fast, satisfying drills. See a number, build the answer on a tappable bit row or a clean keypad, and get an instant verdict with the place-value breakdown behind it. It's built around how you actually learn: a level climb, an ~80% mastery gate, and a three-minute daily habit. WHAT'S INSIDE - The drill — convert decimal ⇄ binary ⇄ hex, both directions. Tap the bits or type the digits, confirm, and see exactly why the answer is what it is. - The nibble block — the standout: see how 0x61 = 0110 0001 = 97, with hex sat over colour-coded 4-bit nibbles. This is the trick that makes hex click. - A level climb — one level per bit, from the first switch up to the full byte (the 256 Club) and beyond. Clear a level test to unlock the next. - Two's-complement — read and write signed bytes, with the sign-bit reveal. - Bitwise ops — AND, OR and XOR, worked one column at a time. - Byte Speed Run — an optional 60-second timed challenge once you've earned it. - Daily goal + streak — a gentle habit, with a streak freeze so one missed day doesn't wipe your progress. - Explore — scrub a number and watch decimal, binary and hex move together. BUILT RIGHT - Fully offline — no account, no sign-up, no tracking required. - A clean, friendly light design in apricot and teal. Remove ads with a single one-time purchase — it removes the interstitial ads, and it's the only thing we'll ever ask you to buy.