German practice that
learns your mistakes.

One tap writes you a set of exercises, marks them honestly, and aims the next session at whatever you actually keep getting wrong. No account, no backend — everything stays on your device.

Needs your own OpenRouter key. Try Mock mode in Settings to look around without one.

How it works

A closed catalogue of 41 mistakes

Every error is tagged from a fixed list — adjectiveEndings, wechselpraeposition, konjunktiv2. Anything the model invents is discarded. That's what makes mistakes from different sessions add up instead of fragmenting into labels that never match.

An essay is worth ten gap-fills

Exercises carry a cost, and a session spends a budget rather than counting items. Weak at writing? You get one essay instead of ten drills — and the errors it exposes become the next few sessions' drilling.

Marked strictly, on purpose

Long writing is scored against the four exam criteria. The marker is told to err on the harsh side, because encouraging feedback teaches you nothing.

Your teacher's feedback, drilled

Paste what your teacher told you. It's mapped onto the same catalogue, weighted up for the next few sessions, and you can practise it right away.

Download

Installing: Android will warn about an app from outside the Play Store — expected for a sideloaded build. Allow your browser to install unknown apps when prompted. The web version needs no install at all, and on Android you can add it to your home screen from Chrome's menu.