NUMEN vs Sumday

"Not solving math — the moment you start to feel it." NUMEN is not a problem-set app. It's an app for everyone who once gave up on math — and wants to recover the sense of it. ■ A different approach Other math apps: Definition → Formula → Practice → Wrong answer NUMEN: Experience → Pattern → Intuition → Definition You touch with your finger. You drag a slider. You watch values change. Each fraction slice, each function curve, each direction of a negative number — every concept comes alive as moving math, not memorized math. ■ Who is this for? · Middle and high school students who lost the thread · People burned out on classroom-style explanations · Adults who want to understand investing, statistics, or AI · Anyone who wants to feel "I wasn't bad at math — the connections were just broken" ■ What's inside · Interactive lessons you actually touch 33 lessons across 10 phases — sense, relations, change, chance, shape, cycles, limit, slope, accumulation, direction · Intuition first, definition later See the phenomenon, find the pattern, then meet the formal name · 5–10 minute daily sessions Light enough to keep, deep enough to transform · Daily streaks A little, every day — that's how sense rebuilds · Four languages Korean · English · Japanese · Simplified Chinese — every lesson body translated · iPhone · iPad universal · Fully offline No ads. No tracking. No data collection. No internet calls. ■ Why NUMEN? You weren't bad at math. Only the connections between concepts were broken. NUMEN was designed — by hand, with care — to reconnect them. "Oh — I wasn't dumb. The connections were just broken." That moment is what NUMEN is built for. ■ Privacy by design NUMEN collects zero personal information. All progress is stored only on your device. No analytics, no advertising SDKs, no external APIs. ■ Pricing · The app itself — free to download · Phase 1–3 (12 lessons, ≈ 60 min of content) — free · Phase 4–10 (21 lessons) — single one-time in-app purchase, unlocks forever. No ads, no subscription, no renewal. ■ Coming next · More lessons within Phase 5–10 · Personal review / notes screen Begin today. Mathematical sense is not memorized — it is recovered.

Five minutes a day to get your mental math back. Sumday is a quiet daily routine for adults: real arithmetic, not puzzles, that keeps your number sense sharp. The more we rely on calculators and spreadsheets, the slower the math in our head gets. Sumday wakes it up with one short set a day that mixes addition, subtraction, multiplication, division, percentages and estimation. Learn one practical math trick a day, the kind school never taught you, and feel your speed come back. WHO IT'S FOR • Adults who feel their mental math isn't what it used to be • Anyone preparing for aptitude or job tests with timed number questions • People who want to split a bill, work out a discount or estimate a total in seconds • Anyone looking for light daily brain training HOW IT WORKS 1. Solve today's set of 20 questions. Five minutes is enough. 2. Check your results: accuracy and response time, compared with yesterday. 3. Unlock today's technique card and use it in tomorrow's set. 4. Come back tomorrow. A daily reminder keeps your streak going. FEATURES • Today's set: 20 mixed arithmetic questions across 7 types: addition, subtraction, multiplication, division, percentages, estimation and everyday math • Adaptive difficulty: questions get harder as you improve and ease off when you get stuck (12 levels) • Daily technique cards: 30 mental math tricks, from rounding shortcuts to quick percentages • Results report: accuracy, average response time and change since yesterday on one screen • Progress charts: daily and weekly trends in accuracy and speed • Streaks and a gentle daily reminder NO ACCOUNT, NO SERVER No sign-up needed. Your records stay on your device, and it works in airplane mode. PREMIUM (OPTIONAL) A one-time purchase removes ads and unlocks 3 practice modes (estimation, percentages, everyday math), Challenge mode (endless survival with 3 lives), detailed statistics and all 30 technique cards. No subscription. Available in English, Korean and Japanese. Start your five minutes of math practice today.