They’re saying because brands dollars are coming in:
On the one side, mobile-first publishers in the casual games, social, and entertainment spaces continue to compete for engaged, profitable users. They’ve already driven the cost of new users up to nearly $3 each, and that’s just the beginning. Engaged, signed-up users can cost $40-200. But now, on the other side, big brands are joining the mobile advertising banquet in droves, seeking new ways to connect to millions of customers.