This puzzle is kind of a graphical hybrid of Sudoku, where you place your pieces of train track to join up the start/finish pieces on the edges, but you are ONLY allowed the count of pieces given next to each row and column.So if a column count is 3, you are only allowed three track pieces in that column.As you click any square, that square will rotate through the allowed puzzle pieces, but it is up to you to make sure the row/column counts are correct. A square will turn to green when a correct row or column count is reached.It is easy to see when youve completed the puzzle successfully, because the whole puzzle will be green.Your score is the ratio of the number of moves you took, versus the minumum possible moves for the current puzzle.This app doesnt need ANY permissions on your phone or tablet. I wrote it to learn the basics of Android development. If it gets any use and not slated in the feedback Ill add more puzzles - at the moment Im not sure if the puzzles are too hard or too easy...