In a mobile monetization report released today, app testing firm Swrve found that in January, half of free-to-play games' in-app purchases came from 0.15 percent of players. Only 1.5 percent of players of games in the Swrve network spent any money at all.
The latter finding is in line with what the advocates of free-to-play have been saying for years: Players don't have to pay anything to enjoy the game. But the former stat underscores the importance of big spenders, or "whales" in industry lingo, to the app ecosystem.
(Read more: What's shaking at the Mobile World Congress)
Not all game companies talk openly about the fact that they have whales. It costs money to develop and keep a game running, just like those fancy decorations and free drinks at a casino; whales, like gambling addicts, subsidize fun for everyone else.