Loopy is one of Simon Tatham's portable puzzles. Draw lines along the edges of the grid to make one single loop with no crossings and no branches. Each number in a square says how many of that square's four sides are part of the loop.
Every puzzle is generated fresh. Besides squares, the Type menu offers grids of triangles, hexagons and other tilings, at several sizes and difficulties.
Controls
Click or tap an edge to draw a line on it; right-click to mark it as definitely empty. The menu bar has New game, Restart, Undo, Redo and…
Genre
Puzzle, Logic, Desktop
Price
Free — no account, no download, nothing to install
Tips for Loopy
A 0 means none of its sides are used: mark them all empty first.
Corners with a 3 next to them often settle quickly.
The loop can never end: every dot it passes has exactly two lines.