iOS 8 Installed on 87% Devices Ahead of iOS 9 Release
Comparatively, the latest version of Android (5.1, aka Lollipop) sits at a 5.1% adoption rate. However, Android updates often take a long time to propagate to customers, partly because cell phone manufacturers and cellular carriers must bake in their apps and interfaces into the operating system.
According to mobile analytics firm Mixpanel, iOS 9 currently holds a ~1.04% adoption rate, which includes public beta testers and developers. That number will likely increase dramatically as the operating system will push to iOS users today, September 16.