How to create sleek customized buttons, tables and other views for iPhone/iPad apps?

I'm looking to know both what can be customized as well as the recommended way to customize some of the major UIView subclasses in the iPhone SDK (in particular开发者_StackOverflow UIButton, UITableView/Cell ... but really open to any of the views in the SDK).

Any recommended tutorials?

Examples?

Are there bad practices that can actually hinder performance and/or destablize your app in any way that should be avoided?

Thanks

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You need to subclass existing elements and use your own graphics. See this: http://developer.apple.com/mac/library/documentation/DeveloperTools/Conceptual/IBPlugInGuide/Introduction/Introduction.html

For practices regarding custom interfaces, read the Human Interface Guidelines.

By the way, this question is dupe: How build a custom control in Xcode for the iPhone SDK?