Bobs Sudoku Solver. Enter the numbers and press Go. Can solve puzzles down to 17 numbers. 
Puzzles with less than 17 characters may have 2 or more solutions....
The app is easy to use. Just tab long using the cursor keys and enter your number. When you are ready press go and it will find a solution. Optionally it will display the number of tries the app took to find a solution. 
The "R" key on the display will take the display back to before you pressed "GO" this is useful to delete numbers to produce a more difficult puzzle? 
The "C" key clears the screen and you can start again. 
Save your puzzles. 
Easy peasy..