How to make partly transparent png-image buttons for iPhone?
My iPhone App has custom buttons that display png-images.
 I like to replace the white color in those images by a transparent color. Is there a tool on the Mac that allows me to do that? (or is there some other way to indicate which color is transparent in xcode?) 
How to make partly transparent png-image buttons for iPhone?
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My iPhone App has custom buttons that display png-images.
 I like to replace the white color in those images by a transparent color. Is there a tool on the Mac that allows me to do that? (or is there some other way to indicate which color is transparent in xcode?) 