Purchased the Nexus 7, cable and adapter, camera is not detected. I tried another app, Helicon Remote, it too did not detect the camera.
I downloaded the OTG Troubshooter, it says yes for USB host support, then OTG detected when that cable was inserted, then Still Image USB devise detected in Linux but no detection in Android. Android 4.3 Issue 58277 Detected

I expect to get my 2013 Nexus 7 today or tomorrow, I will then check and give you feedback.

just got the same problem
Nexus 7 2013 with Android 4.3

the old Nexus did work...

I got my Nexus 7 2013 today, and it's working like a charm. Tested it via WiFi/TP-Link router and USB-Otg cable. No Problems.

Hast Du Android 4.2 oder 4.3 drauf?