Mental Math vs Numvolt

10 minutes a day to keep your mental math sharp. Whether you're in middle school, in high school, or an adult who wants to reconnect with math, Kalc helps you forge solid mental reflexes, without cramming. Spaced repetition system (SRS): concepts you master space out over time, the ones you miss come back the next day. The method known to deliver the most learning per minute practiced. WHO IT'S FOR · UK students (Year 7-10), US students (Grade 6-9) · Other English-speaking systems (Canada, Australia, Ireland, NZ) · Spanish-speaking students (Spain ESO, Mexico secundaria/preparatoria) · French-speaking students (France, Belgium, Switzerland, Quebec) · Adults who want to get back fluency with mental math Each user picks their school system during onboarding. Content and examples adapt. WHAT KALC COVERS · Multiplication and division (times tables, decimals, signed) · Fractions (simplification, operations, fraction of a whole) · Percentages (calculation, increase, discount, compound change) · Powers and square roots · Algebra and order of operations · Addition and subtraction of signed integers TWO PRACTICE MODES · Zen mode: at your own pace, no pressure, to consolidate the basics · Chrono mode: against the clock, to build speed under exam conditions VISIBLE PROGRESS Every skill has its own level and progress bar. You see exactly where you stand and what's left to master. IN REAL LIFE Every session ends with a concrete example of how this skill serves you day to day: splitting a restaurant tab, reading a paycheck, working out a discount, planning a budget. Mental math is something you actually use. HOME SCREEN WIDGETS Track your progress straight from your iOS home screen, without opening the app. Streak, XP and skills in progress at a glance. MEASURED REMINDERS Up to 5 reminders over the first 3 weeks, off at any time. No spam, no guilt-tripping. ONE-TIME PURCHASE, NO SUBSCRIPTION Kalc is free to download (1 skill available without purchase). Full access unlocks with a single purchase (lifetime or 1 year non-renewing). No traps, no hidden paywall. PRIVACY All your data stays on your device and syncs through your personal iCloud account. No ads, no advertising tracking, no cookies. Kalc is for people who want real progress in mental math. Privacy policy: https://lmtdigitalcreations.com/kalc/privacy.html Terms of use: https://lmtdigitalcreations.com/kalc/terms.html

Numvolt helps you get better at mental math: open, calculate, understand, repeat. No account and no ads. For new installations, Numvolt Pro is required to start sessions after onboarding. Choose a yearly subscription or a lifetime one-time purchase; the price and terms are shown before purchase. FIFTEEN TOPICS, A HUNDRED AND FIFTY RUNGS EACH Addition, subtraction, multiplication, division, fractions, percentages, order of operations, powers, algebra, square roots, signed numbers, proportions, time and durations, unit conversion and number patterns. Each topic has its own 150-rung journey, up to five elite chapters; the difficulty adjusts during the session, block by block. You pick your starting point at setup, and you can always replay a lower level. THE FASTEST METHOD, FOR EVERY CALCULATION After a mistake, and at the end of a session for your slowest answers, Numvolt shows you the fastest way to do it in your head, step by step: 71 × 87 is 70 × 87 + 87; 79² is 80² − 160 + 1. With the reflex to keep and other ways to do it. In the courses, type any calculation and the app explains the best method. In Zen mode there is no timer: time to understand. SPRINTS AND A DAILY CHALLENGE 15, 30 or 60 seconds on the + − × ÷ mix. +1 per correct answer, −1 per mistake. The daily challenge is the same 60-second series for everyone, all day long. A LADDER FROM YOUR CITY TO THE WORLD Join the ladder with a nickname and your city. Your best sprint is ranked on six rungs: city, county, region, country, continent, world. After every sprint you see exactly what you climbed — "5th → 2nd · Rhône" — and how many points you need to overtake the next player. Only your nickname, city and scores are published. Never your exact location. DUEL ON ONE PHONE Two players, the same questions in the same order, 30 seconds each. Scores are revealed at the end. YOUR PROGRESS, VISIBLE XP, overall level, accuracy, day streak, seven-day chart, level per topic and session history. A Home Screen widget shows your daily goal and starts a sprint in one tap. WHAT STAYS WITH YOU Your progress lives on your iPhone, in the app's storage. No account. Anonymous usage counters, which you can switch off in Settings, only tell us where the app gets stuck. Fractions and decimals accepted on the keypad. Light, dark or automatic appearance. Available in 46 languages. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/