Zynga’s Facebook smash Farmville, released in 2009, had more than 32 million daily users at its peak in 2011, pushing the company to more than $1 billion in revenue the year before it went public. (Soon after, the shift to mobile punched a massive hole in its user base; in February, Zynga reported a net loss of $209 million for 2012.) On mobile platforms, Angry Birds creator Rovio, with headquarters in nearby Espoo, Finland, made its money by pushing tons of ads to free players, and a little more by charging users an extra buck or two to download an ad-free version. By contrast, Clash of Clans players looking to climb past the first few easy levels are paying $100 a pop for a chest of gems usable as currency in its virtual store; Hay Day’s trunks of gold coins cost $80 each. As Supercell’s coders roll out a new level of advancement for players each month, both games have remained top-five iOS store grossers since December, according to Bertrand Schmitt, CEO of market-research firm App Annie.
Supercell's games “Hay Day” and “Clash of Clans” have both been top-five iOS store hits since December