So many of you have probably wondered why Apple changes the Calculator icon in every major iPhone OS (iOS) release. Well, only Apple truly knows, but here is a good reason why the iOS 3 Calc icon changed in iOS 4. You know that neat new feature called Folders? Well if you notice the Calculators icon in iOS 3 you see that is closely, if not exactly, resembles a Folder on iOS 4. With the white border and textured background it might be hard for SOME PEOPLE (definitely not everyone) to distinguish. As for the original iOS to iOS 2, you've got me clueless as to why they would change the design of the icon. Maybe it was because they used the calculator icon as a representation of what a Folder icon would look like in the future; and the future is now, with iOS 4 and Folders.

-CJ
Post your questions and comments below! I'd like to hear your theories.