We used the app on the Fantasy in June. In the past, we always carried around the navigators to keep track of things. This time, we used the app all the time, and barely picked up the paper copies. We were able to set favorites, and then get a reminder before hand. I actually thought the mixology classes were on the app as well, but maybe I am remembering incorrectly. It was nice to see the menus, and to see what time different places closed at night.
The messaging worked great for three out of four of us. The fourth would sometimes not get messages. As others said, it does not work off the ship, including
Castaway Cay. Our daughters and friends were so used to the app while on the ship, they struggled (just a little bit) when on Castaway Cay and were not able to message each other. We never touched the Wave phones, but did not have any need to call the ship services while wondering around the ship.
To the OP, there is also a station next to DVC sales that has a tech for helping getting your phone to work. Based on your description of it continuing to say 0 days until your cruise, it sounds like you did not get hooked up to the
DCL wireless network. Once you hook up to the network, it downloads all the navigator data.
And a final recommendation. The app also does not work while you are in the terminal. Once you get on the ship (while ship is still at the port), connect to the network. When you open the app, go to your message settings (can't remember exactly what it is called). Each guest has a six digit identification number. Take a screen shot of your number, then disconnect from DCL network and connect to your wireless carrier (you might need to go to a top deck). Share this number in any social networking groups you belong to, and hopefully others in your group also share. Take note of your friends numbers, and enter them in your phone. This way, you can text them directly. You could also share numbers if you have a day 1 meet and greet.