One slide in a presentation by Internet analyst Benedict Evans should really stand out to people in the music business: Ecosystem sizes. The chart shows the growth in the ecosystem sizes over the last three years of Apple iOS, Google Android, Amazon and Facebook. (Evans calls these “The Four Horsemen.”) The first three are important players in the music business. Facebook has an important, but less direct, role in the music business because it does not license music for sale or streaming.

Evans’ chart shows Google Android has topped 600 million users, about 50% more than Apple iOS (400 million) and three times the number of Amazon accounts (200 million). Amazon has grown roughly 50% over three years, while Google Android has gone from zero to 600 million over that time. Apple iOS has grown a bit over fourfold.

Read the full story: Billboard