24 Oct 2009
That means Zynga can quickly find out the impact of small adjustments—such as changing the size of a cabbage patch in FarmVille or the cost of a new gun in the game Mafia Wars—on retaining users and increasing revenue. One recent success: digital sweet potato seeds that cost $5 a packet. The seeds, which of course cost nothing to duplicate, pulled in more than $400,000 in three days.
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Inside the App Economy - BusinessWeek
Cha-ching.