One pebble per territory
Every colored territory needs exactly one placement.
Exactly One · Available
Exactly One
A tactile logic puzzle. One pebble in every row. One in every column. One in every territory. No two may touch.
The idea
Quiet rules. Tactile decisions.
Rows and columns stay unique
No two pebbles can share the same row or column.
No touching
Neighboring pebbles need breathing room, including diagonally.
Launch status
Play Exactly One free on iPhone and iPad. Solve 100 uniquely solvable logic puzzles, take on a new daily challenge, and climb the Game Center leaderboard.