Pick a default iCloud mail alias, disable others [iOS 6]

Apple’s email service, whether it was .Mac, MobileMe, or iCloud, allows you to create aliases as different addresses that still funnel into your inbox.
You can create up to three other addresses—perhaps one for shopping and maybe another for email lists or registering with sites you don’t trust. You can then assign colors to messages sent to your aliases or filters to automatically file them away.

iOS 6 is the first time Apple has paid some real attention to aliases in its mobile OS. If you tap through to Settings > Mail, Contacts, Calendars > [your iCloud account] > Account > Advanced/Mail, you can now set one of your aliases as the default from address for that account and disable aliases from being used on your device.

In fact, if you set an alias as your default from address, you can disable your iCloud account’s primary address.

Note: in my screenshot you see both @me and @icloud addresses. With the move to iOS 6, all @me addresses from MobileMe accounts gained @icloud alternates with the switch to iCloud. These do not count against your three aliases, they’re basically just alter egos to ensure your @me mail doesn’t bounce.