Games account for an estimated 80% of the $10 billion app market value

"Apps are big business, and the biggest app business is games.  In 2012, Flurry estimates revenue earned from apps will approach $10 billion, with games taking over 80% of the pie.  The free-to-play business model (aka freemium), where consumers download and play the “core loop” of a game for free, but then pay for virtual goods and currency through micro-transactions, is the most prolific business model in the new era of digital distribution.  When it comes to app consumption on iOS and Android smart devices, consumers spend over 40% of all their time using games.
The most successful companies in the new mobile economy, from Electronic Arts to Zynga and Mobage to Supercell, deeply understand consumer behavior differences by game genre.  This level of understanding greatly informs a company’s app acquisition, retention and monetization strategies. In this report, Flurry examines the consumer behavior differences by app usage, retention and demographics for the top nine freemium game genres in mobile gaming.  For this analysis, Flurry leveraged a sample of more than 300 million consumers using iOS and Android games each month. Please note that, for consistency, we include only free titles."

Source:  Estimates from Flurry, reported in their blog, 13th December 2012