Google Play grows bigger than Apple's App Store in 2014
blog.appfigures.com
blog.appfigures.com
That said however, look at the categories that have been getting most of those new apps. Games in particular, wasn't a category that was as busy in years before. That to me is where the shift is happening, and I'd attribute it to the success of freemium apps (which is most likely the result of putting Android devices in the use of mainstream users).