Over all this is a decent app. Individually tracking 40,000+ is impressive. The disappointment is that the claimed tracking isn't real-time tracking. It's an estimate with check-in points every 5 k. That brings me to the second strange quirk. It's in Chicago (which uses Imperial measurements), it's advertised as a, "Marathon" (which is 26.2 imperial miles) but the check in points are metric... Like it or not, 90% of American users will not be able to visualize the metric distances and be able to tell where the competitors are on the track. Finally, the app insists of zooming back to my location on regular, 30 second intervals without prompting. As I'm scrolling around the map to see the runner or locations, I would just locate the desired information and the app would zip back to my location. I'd have to go back on the scroll hunt for the information I desired. Basic functionality is good, just some weird things going on in the minds of the developers.

We were thrilled that this app worked so well --- spot on after the 5K point which helped tremendously. It really didn't "locate" our runner on the map until then. It would be nice if splits could be viewed in miles or kilometers. As a first-time spectator we would have LOVED a spectator "viewing route" where it could tell us where to go and how to get there based on our runner's pace. Maybe even preload an anticipated pace to get recommended viewing points!

I tried to track my friend on Sunday. It showed she never crossed the start line then once she got to the 5k point it loaded the start time and the 5k Point then I tried to find her around the 25k point then the 25k line disappeared completely from the app then all of a sudden she was at the 40k point. When I looked at the results at the end the 25k point magically appeared again. If you are going to have an app for 40k + people running you better be able to support that amount of people tracking everyone. Such a disappointing tracking experience.

No way for runners to truly claim a profile, defaults to kilometers with no way to convert to miles, live tracking not very functional, no way for trackers to share real-time messages with runners, and no (easy) way for runners to access messages sent. And it wasn't even released until 3 days before the race. Expected much more from the official app for a world major