Dot & Box
One line. One choice. The whole board.
Close a box. Keep the turn.
Two people share this device. Take turns choosing an empty line between dots. Complete the fourth side of a box to claim it and play again. A shared line can close two boxes at once.
Most boxes wins. Think ahead: a tempting third side can hand your opponent a chain. Use a pointer, or Tab to a line and press Enter or Space.