Analog Digital Clock is an iPhone app designed by Maarten Baas. Actually, it’s just the iPhone version of one of his Real Time clocks which he presented during last years Salone del Mobile in Milan. The clock is actually a film, you can see an actor painting the segments of a giant digital clock black and then wiping them clean again.
So, this is of course a pointless iPhone app but still a very nice one. And $0.99 or €0.79 are worth it.

This is a behind the scene photo, showing you how they filmed it.