A new App Annie report notes that "Worldwide iOS revenue surged in part due to incredible gains in China, the United States and Japan. China was among the most important contributors as iOS downloads grew 20% from Q4 2014 to Q4 2015 and revenue doubled year over year. Google Play made impressive download share gains in the US, as its share of iOS and Google Play downloads combined surpassed the iOS App Store in 2015. The report's graph as noted below shows us that Google Play's worldwide downloads continued to widen to nearly 100% over iOS during 2015.
However, what matters, what always matters most, is who made more money. App Annie's answer to that is clearly seen in their second graph below which shows us that Apple's App Store is still king of profits.
For those interesting in reading the entire App Annie report, simply download it here.