The latest version of Android just hit a big, big milestone. Google’s early June developer stats have revealed that Marshmallow is now on just over 10 percent of Android devices, representing a huge jump from just 2.3 percent in March. Notably, only some of that surge can be credited to people upgrading from Lollipop. While the not-quite-current version’s adoption did go down (to 35.4 percent), the biggest declines in usage were for Jelly Bean and KitKat. In essence: many of those moving to Marshmallow may well have been replacing devices that were 3 or more years old.
Source: Android Developers