The Disintegration Of Android, Visualized. There are some graphs but these three paragraphs say most of it.
"On iOS, for example, an app developer doesn’t need to account for too many variables. Apple has only ever made 15 iOS devices, with a handful of resolutions, clock speeds, and screen sizes to support. Not only that, but an overwhelming majority of iOS users--95%!--is running the latest version of the operating system, iOS 6. It’s this internal cohesion to iOS that makes it so attractive to devs. Most app developers either fly solo or are part of very small teams, so just by testing their app on a small handful of devices running the latest version of iOS, they can reach 95% of the App Store market.
But look at Open Signal’s Android charts. Android’s cohesion hasn’t just been shattered, more than a quarter of it has been blasted to atoms. There are literally thousands of devices any prospective Android developer has to account for. Nearly a third of those devices are still running a two-and-a-half-year-old operating system riddled with bugs and security holes. In fact, only 5.6% of all Android devices are running the most recent and stable version of the operating system, Jelly Bean.
But it gets even worse. Apple only asks iOS developers to support four screen sizes and four resolutions. But take a gander at Android! Any developer who wants to make an app for the Google Play store needs to test their UI across dozens upon dozens of different screen sizes and resolutions. And unbelievably, it’s even more complicated than that, because many of the major Android device makers like Samsung and HTC slap their own custom skins on top of Android. "