By default, when building an application with Xcode, your icon will have a round beveling of the corners and a shine added over the top of the icon. The icon below shows how this looks:
You can override this default by following line to you to the Info.plist file. For example, if you prefer to edit Info.plist as a source file, add the following line:
If you are editing Info.plist as an XML file (in Xcode) you can add an entry that looks as follows:
Depending on your configuration and version of Xcode, the option in the Info.plist file may looks as follows:
With the pre-rendered icon set to true, the icon shown above will now look like this:
This preference setting only applies to removing of the shine / glossy effect, the corners of your icon will still be rounded for you.