Hi Jill,
There is WiFi access now in
some of the Walt Disney World resort hotels (primarily the deluxe and DVC villa resorts), but there is no WiFi in the theme parks. Unfortunately, this makes most of the park navigation and scheduling apps less than optimally useful in your particular situation.
That being said, my overall favorite WDW app is Lines, which is put out by the same team that produces the Unofficial Guide to Walt Disney World and touringplans.com. Lines gives up-to-the-minute notices about attraction wait times and suggests the most optimal order in which to experience attractions. Without WiFi, you use some aspects of this app by checking it a resort at the beginning/end of each day, but the most exciting parts of it would be missing for you.
My friend Marc has some
additional app suggestions that might make sense for you.
Good luck with your planning. Please let us know if you have additional questions.