Ask HN: How long do you support iOS4 before moving to iOS5?
I understand iOS upgrade adoption is quite high, but how long do you wait? Do you force users to upgrade?
Forget about if the newest release of a class is easier for me (the developer) to use, if it doesn't deliver a significant performance advantage to my end user, I ignore the new features and stick with the oldest version still supported.
Obviously I couldn't do that with an entirely new functionality like iCloud, but for something like MPMoviePlayerController? Forget about it.
I know it can get annoying to check the iOS version before every method call, but well designed code can minimize this greatly.
Personally I'll be supporting iOS 4 until a good bit of the stuff I use in it is deprecated by Apple.