Wordoku is Sudoku played with letters instead of numbers. You fill a 6x6 grid so that every row, every column and every 2x3 box contains each of the six letters exactly once.
Tap an empty cell, then tap a letter or press it on your keyboard to place it. A cell turns red if the letter clashes with another in its row, column or box, and Backspace or the erase key clears it.
The difficulty sets how many letters are filled in at the start. Easy gives you the most starting letters and Hard gives you the fewest, so harder puzzles take more working out.
Hit the Check button and any letters that do not match the solution are flagged. Solve the whole grid with no clashes to win.