As well as tracking who is responding, the map view provides the ability to see where your responders are that are using the smartphone app. This instantly allows you to make educated real-time decisions. For example, a fire department member may decide to wait another 60 seconds for additional personnel to arrive to the station because they now know that "Johnny" is a half mile away that would otherwise be missed.
Members have the ability to opt-out of GPS tracking if they are concerned about privacy, however the app will only submit location information once they have indicated that they are responding. Tracking stops either after the callout has ended, when the user indicates that they are "on scene" or "standing down", or after a timeout that the user can choose in the app settings (the default setting is 15 minutes).
This depends on several factors, including the particular model of phone being used, and the strength of the satellite signal being received. In most cases, however, the position is accurate to within a radius that is small enough to determine what building the responder is near to.
The GPS tracking feature transmits a small packet of data intermittently, once every 5 seconds. For a 30-minute callout, this will use approximately 150KB of data, which is roughly equivalent to a single average-sized web page.