Clear the board by matching pairs of identical tiles. A tile is free if nothing covers it and at least one side (left or right) is open.

• Tap a free tile to select it, then tap its matching free partner to remove both.
• Tap a different free tile to change selection.
• Hint highlights a valid pair (limited by level).
• Undo restores the last removed pair (limited by level).
• Reshuffle redistributes remaining tiles on the same slots.