Google Camera seems slow and laggy sometimes. Has this been happening on earlier N versions, too? The app just froze for a good two seconds at start up. Course I don't know if the lag was coming from the app itself or the fact that I flipped the phone to landscape while the app was focusing. Still, it was slower to start than I've ever seen it.
I am not having any problem with camera on DP4 - and did not have any problems on DP3.
NEXUS 5X on AT&T on N Beta