It is not a third party app. The clock is essentially part of the skinning or "look" of your phone. Do a search for "Flip Clock" and see what you get. There are numerous files around here that have many different clocks (most of them flip). Look in the threads that are directed at the Touch Pro or Diamond like the one here . . .
https://www.wckediden.com/showthread...hlight=keyswop
The files you download, if they're cab, then just install on your phone normally, but be sure to disable TF3D before you do. And if it's just files, drop them into the Windows folder using Resco Explorer or Total Commander and override the files. Good luck.