Touch the letters in the grid to make a word, then click 'Submit' to save that word.
Tap 'DEL' to delete letters from the current word, or long-click to clear the entire word.
To search a word's definition, select the word in the list.
When the timer runs out, any words you missed are displayed. Or if you're not in a timed game, select 'Score' from the menu to see how you did.
Any current game will be saved whenever you leave the application.