allowing the D1 to count the number of digits that have flipped over and thereby deduce the current state of the display. There’s plenty of fun to be had with classic flip clocks like this ...

While there's no official Flip Clock offering from HTC on the Play Store, a number of third-party developers have crafted ...

Earlier this year, we mentioned in a Hackaday Links article that [Spencer Hamblin] was in the process of building a seven-segment flip clock. Well, it’s finally finished, and it looks great!