While the language is nice, I find it hard to work with existing frameworks, given they are designed for a language as dynamic as objective-c.
For example, NSError, NSNotification&#x27;s userInfo is a `[AnyObject:AnyObject]`, but its member types are specified in documentation. It would be nice if we can have specific error will typed userInfo. Working with storyboard is the same story, there is no type check for VC and segue because identifier is a string, instead of something like `R.id.view` on android. Working with this kind of API requires lots of casting, I wonder will Apple design Swift-centric API later.