Elevate how you calculate.
The intelligent mental-math app for iPhone and iPad. From basic arithmetic to number theory, fully offline.
Heads-up: the app's interface is currently German-only. More languages are on the roadmap.
TauState is an intelligent mental-math training app for iPhone and iPad, built for anyone who wants sharper mental arithmetic. It offers 8 game modes and more than 40 operators, spanning the four basic operations, percentages, powers and roots, number theory, and number systems like binary, hexadecimal, and Roman numerals. Difficulty adapts automatically to the player's level, and a fully configurable Lab lets you build custom training sessions around exactly what you want to practise. TauState runs completely offline, with no accounts, no ads, and no tracking, and even its on-device speech recognition never leaves the phone. It's currently free during the TestFlight beta and requires an iPhone or iPad running iOS 18 or later. This website is available in German, English, Spanish, and French, though the app's own interface is German-only for now, with more languages planned.
Three ways into the app.
Why mental math is trainable
Not a talent, a muscle. The philosophy behind TauState, and why calm daily practice beats perfect runs.
Read the philosophyEverything that's inside
8 modes, 40+ operators, number systems, the Lab, statistics, achievements. An overview of everything TauState can do.
See the featuresPlay a round in your browser
The four basic operations in the real interface, right here, no install. Three lives, combos, high score.
Start the demoYour data stays your data.
No accounts, no ads, no data collection. TauState works fully offline, even speech recognition runs on your device. What you practise is nobody's business.
Read the privacy policyReady to elevate how you calculate?
Free on TestFlight. iPhone and iPad. Private by design.
Join the beta