As you use iOS, you’ll come to notice a variety of labels throughout the user interface that display redundant or non-useful information, such as the Status Bar's carrier text, the Lock screen’s ‘Press home to open’ text string, and Notification Center’s ‘No New Notifications’ text.
If you aren’t jailbroken, then you can’t customize any of these labels, but if you are, then you can take advantage of a newly-released and free jailbreak tweak called Label by iOS developer archergs to do just that.