As more models are launched and new versions of the OS are published, there will be more fragmentation. This is expected and the odds are that it will happen to

As more models are launched and new versions of the OS are published, there will be more fragmentation. This is expected and the odds are that it will happen to Apple too. Take a look at Symbian, where not only do you have different resolutions, but touch and non-touch phones and a myriad of OS update versions. Luckily, you have access to a virtual device hub where you can do online testing.