What's wrong with fragmentation?
While satisfying news for Google and Android fans at a higher level, the numbers demonstrate just how fragmented the Android market really is.
And how much of this is a problem? The Android API has been pretty stable for the last couple of years and I've yet to come across an app that won't run on any of my three devices, the oldest of which is nearly three years old and it's still on Android 4.0. It's true that this wasn't the case initially with the API expanding rapidly and often requiring stuff in hardware that older kit didn't have.
As others have pointed out in the Windows world there is XP, Vista, 7, 8, 8.1 plus the server versions. The vast majority of software runs fine on all those versions. However, you are generally up shit creek without a paddle if you want to straddle the 32-bit / 64-bit worlds easily on Windows. And don't mention ARM. If you want an example of fragmentation look no further than that.
In the IOS world a lot of developers march neatly in lockstep with new releases and quickly require the newest version of IOS. I'll admit I don't have first-hand experience of this but a mate of mine with quite a bit of Apple kit complains about it regularly. One of the reasons why it's done is because it's a nice way to force paid for upgrades. And if it works for people - that Apple punters are happier to part with their money than others - then good luck to them.