Duo
Fill the grid with two symbols — never three alike in a row, and every line balanced.
Four logic puzzles.
One new set every day.
Hand-verified puzzles that get harder as the week goes on. No ads, no accounts, no tracking — and it works offline.
Free · iPhone, iPad and Android
Four ways of thinking
Plots
Cut the board into rectangles, each exactly as big as the number inside it.
Stars
One star in every row, column and region — and no two may touch.
Bridges
Join the numbered islands with bridges until everything connects, with no crossings.
Always fair
Every puzzle is checked by a solver: exactly one solution, reachable by logic alone. You never have to guess.
Private by design
No servers, no analytics, no sign-in. Your progress stays on your device.
Easy on the eyes
Dark mode, and colour-blind safe: shapes and borders carry meaning, never colour alone.