A trip to Walt Disney World is always about being efficient with your time. If you "just wing it", you'lre going to be looking back on your vacation as a lot of wandering around. The MyDisneyExperience app helps with all of this, but it can also be frustrating.
I have to advise that everyone get this app. It's the first thing every cast member asks when something techno goes wrong (and it will).
I liked the feature giving updates on wait times. It was fairly easy to add fastpasses. Was great for keeping you advised of your dining reservations, upcoming fastpasses, etc.
The map feature could be improved. I need a map that rotates with me in my direction as I walk, not stays constant and you've got to figure out which way to turn.
It took me a couple of days to consistently find the links to things I thought were essential from the main page (my dining plan count, my hotel bill, etc.).
You've got to get this app BEFORE you go to Orlando and start playing with it, even though you're not onsite. I think that's really critical.