Thread safety of UIImage

Question

I know that Apple officially recommends UIKit to be used in the main thread only. However, I\'ve also heard claims that UIImage is thread-safe since iOS 4.0. I cannot find

Answer 1

In the What's New in iOS: iOS 4.0 release notes, the UIKit Framework enhancements include this bit:

Drawing to a graphics context in UIKit is now thread-safe. Specifically: The routines used to access and manipulate the graphics context can now correctly handle contexts residing on different threads. String and image drawing is now thread-safe. Using color and font objects in multiple threads is now safe to do.

So UIImage is thread-safe on iOS 4.0 and later.