The appropriately titled, "Combo Update," adds a whole new brawling mechanic to the player's arsenal. Successfully landing six consecutive punches from alternating sides will unlock a stamina boost that allows for up to three additional strikes. This should hopefully help simulate the adrenaline boost that a fighter would get when pummeling an opponent into submission.
Real Boxing usually costs $0.99, but it is currently on sale in the App Store for free. So be sure to not miss out on this limited time offer.