AppleInsider explains Apple's recent patent application:

For example, if a user needed to visit the Department of Motor Vehicles, Apple's technology could determine which office has the shortest lines at any given time, and advise the user to visit that location.

In the event that the location cannot be changed, such as when the user has a flight scheduled, Apple's system could alert the user with reminders and give them a suggested time to arrive at the airport. Doing so would allow users accommodate for heavy traffic and help ensure that they arrive at their gate on time.

Apple's system would measure traffic by tracking data from a user's iPhone, measuring their movement over time. Those movements would be used to determine how long it takes for people to move through a specific location, estimating how long the lines might be at that particular spot.

"The server can determine how long mobile devices (and their users) loiter around locations of interest or remain in a queue," the filing reads. "For example, the server can analyze the indoor traffic information to determine how long (e.g., on average) mobile devices have to wait near a cash register location."

There is much more that can be done with indoor mapping than just mapping out shopping malls and having nearby stores push promos to your phone.

Apple may never catch up with Google Maps for outdoor mapping, so now, as I've said before, Apple wants to be the Google Maps (and Waze) for indoor venues.