Strategy Analytics forecast the global smartphone installed base will grow +5% YoY in 2020. Android will maintain the top spot as the world's most popular platform, followed by Apple's iOS. However, the momentum of Android platform would be undermined as we forecast Huawei would formally extend its own OS to smartphone domain in 2020 / 2021 as earliest. Apple iOS however is less impacted and its position is likely to be strengthened since next year, thanks to the launch of low cost iPhone SE 2 and new 5G iPhones in 2020. This extensive report forecasts the global smartphone installed base, by 15 operating systems, for 88 countries worldwide, from 2007 to 2024. 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.