When you tap this help button, an helpstep is generated by the solver (if possible), and displayed at the right of Sudoku

When you modify a cell value, a candidate, when you cancel a value or you use color help, a new help-step is added.

This allow you to follow your work and to easily come back to correct a mistake or a wrong supposition.

The arrows allow you to navigate between steps and display progressive clues that allow you to learn new techniques.

You can use this help-step to come back in your research of the solution

Watch out !

If you do an action on the sudoku, value choices, candidate or color, all actions situated after this new one are deleted

You can color the helps by drag & drop with color-button.

So you can find your actions when you'll test values

Build the entire sudoku-solution with this button.

This does not prevent you to go back to work concepts. On the contrary!

When you save a sudoku, your progress is saved automatically

By a double tap on a modified box, you can access Help Step

So you can easily go back and understand how value was determined