OddEvenFilter is a number reflex game built around simple math rules. At the top of the screen, the game tells you whether to tap ODD or EVEN numbers. Random numbers then appear across the play area, and you must quickly tap only those that fit the current rule. Tap a number with the wrong parity and you lose a life. After three mistakes, the game is over. The rule can change as you play, and numbers refresh faster at higher scores. Stay alert, read the rule every round, and keep your fingers ready. It is easy to learn but hard to master when the pace picks up.