Nah there was no app.  Just put the ID in a slot and it look into a camera.  I assume they have closed-loop software that does image matching.

With the guy behind the booth, I'm sure I could have asked them to do a manual verification instead. 

 Gotcha. In DC I heard it was a contractor called "Clear". They make you get their app and everything. But they entice you with TSA pre-check if you facial scan using your phone in the airport instead of waiting in line.  

 Oh I've seen clear.  I don't like the look of it.  This is different though, it's for the standard security checkpoint.