One puzzle a day
Mental math,
daily.
Everyone in the world gets the same ten problems each day. Three minutes, one attempt, your time against everyone else's. Then practice that actually aims at your level — not the average one.
No ads · no streak guilt · works offline
The ritual
Ten problems. One attempt.
Same for everyone.
The daily resets at midnight in your timezone. Finish it and you get a grid worth sharing — where you were fast, where you were slow, where you missed — plus your percentile for the day.
A real ladder
Warm-up, arithmetic, percentages, money, an estimate, and a finisher that earns its name. Never ten of the same thing.
Honest timing
The clock runs from the moment you start. Step away and it keeps running — so the leaderboard means something.
A streak you can miss
One free freeze a month covers a day you lost to life. No red banners, no guilt-tripping.
The trainer
Practice aimed
at your level.
A two-minute check at the start places you on a 0–100 scale. From there every task targets the edge of what you can do — hard enough to matter, easy enough to finish.
Race the clock
60, 90 or 120 seconds. As many as you can take.
No timer
10, 20 or 30 problems at your own pace.
Tips, splits, discounts
The arithmetic you actually do at a table or a till.
Mistakes come back
Not the same problem — the same kind of mistake, after 1, 3, 7 and 21 days, until it stops being a mistake.
Pricing
The daily is free.
Forever.
So is unlimited Sprint and Zen. Premium buys the quality of practice — difficulty that tracks you, the review queue, every mode and your full history.
Three days free, then $4.99 every week.
3 days free$0.77 a week, charged once a year.
Save 85%Cancel anytime in the App Store. We send a reminder before the trial ends — no silent charges. Refund policy.
What we don't do
No ads. Not one.
Not in the free tier, not between rounds, not ever. There is no ad network in the app and nothing to skip.
We do measure which channels bring people who stick around, which is why iOS asks about tracking on first launch. Say no and everything works exactly the same — the app never withholds a feature to punish a privacy choice. Details in the privacy policy.
Questions
FAQ
Is this a brain-training app?
No. We promise one thing and it is measurable: you get faster and more accurate at mental arithmetic, because that is exactly what you practise. No claims about memory, IQ or focus.
What happens if I leave in the middle of the daily?
Nothing is lost — you come back to the same problem. The clock keeps running, though, so a long break shows up in your time.
Does it work offline?
Yes. Problems are generated on the device, so the daily and all practice work with no connection. Only the daily percentile needs the internet, and it syncs when you are back.
Why does my percentile say "—"?
Because too few people have finished that day's puzzle yet. A percentile from a handful of players is noise, so we show your time instead until the number means something.
Do I need an account?
No. There is no sign-up, no email, no password. Your progress lives on your device.
How do I cancel?
In the App Store, under your Apple ID subscriptions — the same place as every other subscription. There is a direct link in the app's settings.