Hidden Mickeys has an app. $8 in the itunes store. Cheaper than buying the paperback and uses your phone's GPS to show you the closest ones to where you are at the moment.
Undercovertourist has a free app and then they have another one which is similar but has more features. The free one works just fine for me.
Disney World Dining app for $2 has menus and locations. You still have to call to make reservations or use Disney's online reservation system. Some recent comments are saying that the menus and prices are out of date for a few of the locations. So I don't know if it is as useful as it was when I was there last.