This Sudoku app is written in Perl using Perl Tk for the GUI and C with GCC for the solver. It will solve Sudokus, generate solvable Sudokus, and lets the user enter Sudokus from external sources like a newspaper. Sudokus that are generated may be solveable with or without guesswork. The solver can be configured to use or not use guesswork (backtracking). Sudokus can be printed to EPS files to obtain a paper copy. Tested with Linux (Ubuntu and openSuSE Leap) and some older versions of Windows (Strawberry Perl 5.30.3.1 32 bit).