Under International Settings, there’s now a new Calendar option, allowing the user to select not only the Gregorian (A.D.) calendar, but also the Buddhist, Republic of China, and Japanese year-numbering systems. For the Japanese calendar, which is divided into eras (the current being Heisei/平成, which began in 1989), depending on whether your region format is set to Japan or not, it will even display the name either in Japanese or romanized.

Further, the Japanese kana keyboard (rather than the QWERTY one) now features a new button: the bottom-left button, used ordinarily for adding dakuten (the “voicing” marks) and other character modification, now does double-duty when there isn’t something to modify. When there’s nothing to be modified, the button changes to have “^_^” written on it, and pressing it will bring up a long list of text faces, from the simple to the quite elaborate.

Finally, though this isn’t a new feature in iOS 4.0, during the 3.x days, Apple added a feature that automatically parses phone numbers properly. While this likely affects nearly (if not every) country in the region settings, if your iPhone’s region format setting is set to Japan, then phone numbers will automatically be broken up appropriately according to area code. This is valuable, as area codes in Japan are of inconsistent length (e.g. Tokyo is 03, whereas the entire northern half of Fukui prefecture is 0776), and the phone numbers are broken up appropriately as well. As a result of this, dialing “08012345678” will automatically break it into “080 1234 5678,” and dialing, say, “0572551234” will break automatically into “0572 55 1234.” Given that even phones sold for the Japanese market by most carriers just lump the whole phone number into a giant block of digits, this is an awfully nice touch by Apple.