The document summarizes key trends in the mobile app market in 2015. It notes that Google Play saw significantly higher download growth than iOS globally, driven primarily by emerging markets like Brazil, India, and Indonesia. Meanwhile, iOS widened its lead in total app revenue. Specifically, China saw huge gains for iOS, more than doubling its revenue from 2014 and surpassing the US as the largest market for iOS downloads. The US remained an important market but saw Google Play downloads exceed iOS downloads for the first time.