99%
Invisible widgets work on the lock screen! I got this because I wanted an invisible item above the time on my lock screen. The iPhone by default has the full date (Saturday, April 27), and anything else one adds shortens the date (Sat 27) and adds other information after it (next event, alt. calendars, time zone, &c.). Selecting this app shortens the date but adds nothing after it, which gives it a nice minimalistic look, which I like.