If you want the biggest time display possible... you'll need to go even bigger than your screen! This app lets you put multiple devices side by side, each showing one digit of the time, to make the largest time display possible.

Perfect app to get a big digital clock display. You'll need more than one phone though. :)

Permissions information
This app uses the standard, Google-supplied, quality and metrics checking code that reports back statistics. To do this, the Google code needs both of:
-view network connections
-full network access