[gks]

Right, I don't think "built-in features" are fragmentation.

If I have to change the way I write my application or can't include features in my application because most users don't have access to the APIs then that is part of what I'd call "Fragmentation."

When only a fraction of your users can take advantage of certain APIs then you have an issue.

I think it's perfectly acceptable that built-in phone features may be limited. You didn't expect to be able to keep the same phone for 10 years did you? Things change.

But two years is the standard contract length in the US. I'd expect phones to get updates for two years so that I can at least target the new APIs and gracefully handle it.

If I designed an app for Android, I'd have to target 2.3 because so few users are on ICS. But with the iPhone I can target iOS 5 and get a majority of users.