I always chuckle a little when I read analytics that say android has most of the mobile market share. While this 'technically' might be true, most of the time those statements are left open ended. What they should say is 'Android has most of the mobile market share including installs on one-of-kind devices, kitchen appliances, watches, $59 tablets, photo frames, automobiles, and other such devices.' The point I'm trying to make is that android is in a lot of places but is not policed by anyone and that is starting to create some problems for Google.
Some are arguing that the Android platform is getting a bit too complex and Google is struggling to keep up with OS updates to keep everything stable. Android doesn't lend itself to 'one-size-fits-all' OS update solutions like iOS does, and it's largely due to the sprawl of the Android device inventory itself.
When a new Android OS release is available, it might work well for your particular device, and might not – causing some 'patch' release updates soon after OS updates to fix problems that were created by the OS update itself on particular devices. It's becoming an endless 'update cycle' for some.
It's an almost dizzying problem and the argument that Android is getting too complex to keep up with the OS issues might valid unless Google can somehow standardize the device platform.