So, we need to use region monitoring. I noticed that commenting out the startMonitoringSignificantLocationChanges doesn't change the Regions sample app behavior.
Actually, I don't deeply understand what it actually does, and how can I tell if a specific location (a few meters sensitivity) was visited if mobile cells are located hundreds of meters away from each other.
It seems that region monitoring is calling the didEnterRegion and didExitRegion as expected, and I don't see the point in the sample app to harness significant location change(SLC) as there is no treatment in the app delegate's in the case of launchOptions containing UIApplicationLaunchOptionsLocationKey.
To my understanding, SLC should be used only when the app needs to know that the user has changed location, and can voluntarily requestLocation to get the new location in the didFinishLaunchingWithOptions if in background.
Region monitoring and significant location changes are different.
Region monitoring creates "geofences" around a location and causes the system to send you messages when the device enters/exits the defined region. Region monitoring is specific to a particular location.
Significant location change monitoring lets you get notified when the user moves a significant distance, but using less power than keeping the GPS "lit". SLC monitoring is not tied to a specific location.
Region monitoring does not require SLC monitoring, and vise-versa.