Plus-Minus
Warning, this game is for the human calculators only! Kidding, anyone can play this game, as long as they have the patience and the math skills. This is another game available for the iPhone. On the screen you will find numbers in boxes and empty boxes in between them. You will have to fill the empty boxes in between the numbers with either a plus sign or a minus sign. The key here is to look at the number after the empty box or look at all the numbers in the rows and columns. Usually at the end of each column and row, there’s that goal that you have to reach, which is zero.