AppCraver writes: "The concept of CryptArithm is easy. You're presented a board with various symbols (including one digit on the easier levels) arranged in mathematical operations. Users must replace each symbol with one of the digits 0 through 9, so that the mathematical operations are correct across each row and down each column. Gamecentric's website has a quote calling CryptArithm a cross between sudoku and algebra, which I think sums it up (math pun!) quite accurately."