"Exit" – on tapping the icon you will be returned to the screen where you started the current puzzle.
"Lock" – tap it to lock scrolling and zooming of the game board. This option will be useful when you are focusing on a particular area of the puzzle.
"Theme" - tap it and select one of nine colors of background.
"Clear" – tap it to clear the game board from single puzzle pieces.
"Hint" – if you are stuck tap this icon and get a hint. You will see some pieces of the puzzle put together.
"Preview" – tap this icon to see the full picture.