Easy SUDOKU 4x4,6x6,7x7 with Secret Tools

Easy SUDOKU 4x4,6x6,7x7 with Secret Tools Do you want to strengthen your kid's thinking ability? Why don't you train your kids' head by doing puzzles with some Doraemon's secret tools? That is the origin of the development of this application. I hope children would have fun playing with SUDOKU, train the brain, and acquire thinking skills. It also becomes a brain train of elderly people. There ar…