With the runaway success of Candy Crush Saga, it's perfectly natural to wonder just how many people are dropping coin in freemium mobile games. One firm's answer, however, might surprise you. A very small number -- 0.15 percent, to be exact -- of total mobile payers contribute half of monthly in-game revenue, according to in-app marketing company Swrve. The outfit also says that over 60 percent of the money made within the first two weeks of a player's life is made on the first day. Meaning, if most people install a game and don't make any purchases almost immediately, they likely won't at all. The report comes from a limited sample, but designers hoping to build the next fragile confection-like phenomenon are probably studying it for secrets right now.