iPhone tab bar Item image resolution?

what is the resolution of the image for tab bar item? and also please provide some other usefull information regarding that tab item image.

Thanks in advance.

From stackoverflow Amit Vaghela

• Check the "UITabBarItem Class Reference" in the SDK documentation

  From Dre

• The documentation says that the tab bar image is usually 30x30, but I've found that the best size to setup the images is 48x32 pixels. This size still renders and gives you a bit more space.

  The image is a PNG with transparency, only the mask is used. The UI renders the mask gray when unselected or blue/chrome when selected.

  From lajos

• http://developer.apple.com/iphone/library/documentation/UserExperience/Conceptual/MobileHIG/IconsImages/IconsImages.html

  From philfreo