Kropki
Fill a Latin square and satisfy the black and white dots between neighbouring cells.
Controls
Fill every cell with a number from 1 to N so each row and column contains every number once. A white dot joins two orthogonally adjacent cells holding consecutive numbers. A black dot joins two adjacent cells whose numbers have a 1:2 ratio. Every such adjacent pair is marked, so unmarked neighbours are neither consecutive nor in a 1:2 ratio; a 1 next to a 2 may carry either dot. Tap a cell, then tap a number to place it; use Clear to reset and the answer button to reveal or hide the full grid.
Brain training · PuzGo