Draw a single path that fills every cell. Follow the numbered cells in order. If the grid has walls, your path cannot go through them.
Press on the end of the path and drag through neighbouring cells. Tapping a cell next to the end also extends the path by one.
To erase, drag back over the path or tap any cell already on it. Undo reverts the last stroke, Clear starts the path again from 1.
Hint erases back to the first wrong cell and reveals the next correct one. Hints are unlimited but counted, and a solve that used one does not set a best time.
Every puzzle has exactly one solution. Today's puzzle is the same for everyone on the same day. Best time is kept per size. Puzzles save automatically.
Keyboard: arrow keys extend the path, Backspace erases one cell.