Subscribing to location changes
One way of subscribing to changes in a user's location has already been covered in the previous section of this chapter. When you call startUpdatingLocation() on a location manager, it will automatically subscribe to the user's location. This method of tracking a user's location is excellent if you need very detailed reporting on a user's location, but usually, you don't need this level of detail. More importantly, using this kind of location tracking for an extended period will drain the user's battery.
Luckily, there are better ways to monitor location changes. One way is to subscribe to locations that the user visits by calling startMonitoringVisits(). This method is used if you aren't interested in the user's detailed movement but only want to know whether the user spent an extended period in a particular area. This type of tracking of a user's location is perfect if you need a low-power way to track...
