SudoKey

SudoKey uses a variety of solution methods -- constraint programming, stochastic searches and backtracking -- to solve standard puzzles. It can be run in two modes: (a) the Just Solve mode to solve the entire Sudoku, and (b) the Row-By-Row mode to get solutions for a single row as a hint to solve the puzzle manually. The algorithm solves Easy to Evil level Sudoku puzzles, but does not solve Diabolic Computational puzzles {due to the limited processing power on your Android device}. The author does have a full-powered algorithm on his computers to solve Diabolic Level puzzles, and he would be happy to try and solve such a puzzle (and maybe refine his algorithms).