High resolution UI Elements for iPhone 4 (Tab Bar buttons...)

where can I 开发者_JAVA技巧find high resolution version of standard iPhone UI elements (like UITabBarContacts.png). I have found low resolution version of icons on some site. I need them becasue I would like to upgrade my app for iPhone 4.

Thanks!

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I'm not sure if this is what you are looking for, but the only place I've found quality UI graphics are from these guys:

http://www.teehanlax.com/blog/2010/02/01/ipad-gui-psd/

and

http://www.teehanlax.com/blog/2010/08/12/iphone-4-gui-psd-retina-display/

and

http://www.teehanlax.com/blog/2010/06/14/iphone-gui-psd-v4/