The global smartphone installed base will grow +6% YoY in 2019. Android will maintain its top spot as the world's most popular platform, followed by Apple's iOS. Tizen's momentum has gone and it has completed phased out. We forecast a flavor of China's own home-developed smartphone operating system will emerge from roughly 2020 onwards. This extensive report forecasts the global smartphone installed base, by 14 operating systems, for 88 countries worldwide, from 2007 to 2023. Almost every major country worldwide is covered, including United States, China, India, Indonesia, Japan, South Korea, Russia, Brazil, Mexico, South Africa, Saudi Arabia, UK, Germany, France, Italy and Spain. This report can be used by operators, software developers, content developers, handset vendors, component makers, car manufacturers and other stakeholders to determine the size and growth rate of the huge global smartphone OS market.