Purchased a 2016 Leaf SV this past weekend.
For me, I got the "authorization successful" message in my car after entering the user ID ("PIN") and password provided by Nissan Owners Portal. But when I tried to use the app I get no success. On the Owners Portal (web site), it tries to connect to my car but always times out, saying "make sure your car has cellular access and that you've driven it in the past 14 days".
I'm currently parked in an under-building garage, so maybe the cell coverage is not the best, but it was apparently good enough for the car to connect and get "authorized" in the first place, so I'm not sure why it was able to do that but not any of the connectivity features via Owners Portal or the iPhone app.
EDIT!
The next day, I tried to connect via the Owner's Portal, and was successful! I can now view my Leaf status, even on the 1st floor of our under-building Parking garage, from either the web site or my iPhone app. Guess it just needed a day or two for everything to register.
Note: the Nissan Connect EV iPhone app is a DIFFERENT APP from the Nissan Connect iPhone app. You need the EV one to do the pre-conditioning, route planner, and other stuff.