As I alluded to earlier today, Sean Patrick O‘Brien and I are working on the very first Mac application that will be released under the Cocoia ‘brand’: Composition. Composition allows you to take any image and get a pixel-perfect preview of iPhone’s default effects at regular home screen size and Settings/Spotlight small icon size. It also lets you look at your icon in a virtual home screen to achieve a native look (and yes, both iPhone and iPod touch home screens will be represented), and export it for further usage on websites and other materials.
Composition is not an icon generator or designer in any way; it is made for people who care about the way their icons look, and want to get a break from the horrible workflow of mashing previews of icons together in Photoshop. There will be several easy-to-access Photoshop templates accessible from the app, but the actual design work is left to applications that are excellent at that kind of work. It will also be completely free!
I will announce more news about it as the application nears the beta milestone; in the mean time, drop an email to this address to get a spot on the list.