Sums: Mental Math Practice

Ten problems. One attempt. The same ten for everyone on earth today. Sums is mental math for adults who got tired of being the person who reaches for a calculator to split a bill. So the whole app is a calculator — an LCD, keys that press, a lime equals — and you're the one doing the sums. One shared puzzle a day, then practice that actually aims at your level. THE DAILY A new set of ten drops at midnight, local time. Everyone in the world gets the same problems from the same seed. You get one attempt, and the clock runs from the moment you start — step away and it keeps running, which is what makes the number at the end mean something. Finish and you get your time, what you got right, where you were fast, where you were slow, and your percentile for the day. Then a card worth sharing: your marks and your time, nothing about the answers. Free forever. It's the whole point of the app, not a sample of it. PRACTICE Eleven modes, infinite generated problems, no content packs to buy: • Sprint — as many as you can in 60, 90 or 120 seconds • Zen — no timer, accuracy only • Survival — it runs until you miss one • Skill — drill one thing until it's automatic • Automatic — the skills you get right but slowly, until they're quick • True / False — 47 × 6 = 272? Yes or no, fast • Missing — 47 × ? = 282 • Money — tips, splits, discounts, unit price, in your currency • Chains — 17, +8, ×2, −5, and go • Clocks — read the dial, estimate the angle, count the minutes • Review — the error patterns that are due today STREAK The streak counts completed dailies, nothing else. One free freeze a month covers the day life got in the way. No red banners, no guilt. WHAT YOU WON'T FIND No ads. Not fewer ads, not ads-only-in-free — there is no ad network in this app at all. No lives, no energy, no coins, no cartoon mascot. No account to make. You play anonymously from the first tap. Every mode and every daily works offline. PREMIUM Free gives you the entire daily and unlimited Sprint, Zen and Survival. Premium changes what practice does for you: • Adaptive difficulty in every mode — problems that land at the edge of what you can do, instead of an average of everyone • The review queue — mistakes come back as patterns on a schedule, not as the same problem again • The full breakdown after every run, and deep stats: your error profile, your median time per skill, your daily history • Skill, Automatic, True/False, Missing, Money, Chains and Clocks modes • Daily archive: replay the days you missed • Unlimited streak freezes and one repair a month Sums Premium is $4.99 per week with a 3-day free trial, or $39.99 per year in the US; the price for your region is shown on the App Store. Payment is charged to your Apple Account at confirmation. It renews automatically unless auto-renew is turned off at least 24 hours before the period ends; your account is charged for renewal within 24 hours of the end of the current period. Manage or cancel anytime in your Apple Account settings — we also send a reminder 24 hours before a trial converts, because a short trial without a warning is a trap. Terms: https://sums.day/terms Privacy: https://sums.day/privacy Sums makes one promise: you will get faster and more accurate at arithmetic in your head, and you'll be able to see exactly how much, per skill. Nothing about IQ, nothing about your memory, nothing we can't show you in your own numbers.