I've had so much trouble in the last year with this app not working, with 4 different TCU swaps since the original $199 upgrade to 3G, that I've finally given up in despair on a permanent fix.
Often, the programming just disappeared from the TCU and display screen, causing a dealer visit to fix/reprogram. Everybody (Nissan, dealer) points at weak cell reception & 3G service "going away" for the communication problem or my 12v battery was low, wiping programming. One person here posted their TCU drained their 12v battery - didn't know the TCU could actually be the cause, just that there was some association. I've gone to placing a battery maintainer on my 12v.
Also, Nissan Consumer Affairs says they rarely hear of this problem; Nissan Customer Service says they have occasional issues. I hadn't checked here for a problem thread. Its existence is proof of a huge debacle with this, contradicting the "it never happens" or "we've done all we're supposed to do" responses from Nissan and my dealer. I feel somewhat redeemed that I'm not an albatross in my "search for a cure."
FYI, last week, after having investigated my full case with my dealer, Nissan Consumer Affairs determined the best way to placate me was to give me a $199 service credit for my original 3G upgrade copay. Perhaps everyone who paid for an upgrade should rant to Nissan Consumer Affairs to see if they're offered this service credit. After shelling out multiple credits, Nissan may acknowledge this problem isn't a rarity.
Oh, BTW, I got an updated status this morning (wow, it worked - what fine cell reception in my garage!).
2012 Cayenne Red LEAF SL: Vanity Plate - G'BYGAS
Reserved 08/10, Ordered 3/12/2012, $99 Refunded 5/16/12, Delivered 6/4/12.