Dixie Champagne
Handy dandy app, especially if you're Southern & have never visited Detroit, but you want to cheer on a friend who's running the race. Course maps are available, but my favorite feature is the ability to search for runners by name, bib #, etc., then track their location on the course, split times, and finish line ETA. One is asked on the start screen whether one is running or not; since I wasn't, I have no idea what's behind door number two.