YoY Share definition Flag Typically a typo made by iPhone 4 users because their phone screens are so pathetically small iPhone 4 user: I love YoY Decent phone user: lol, "YoY" iPhone 4 user: fuck sake, shitty keyboard YoY by xbox_bash May 18, 2015 0 0 Get merch Get the YoY mug. Buy Now — $32.95 See more merch