If so then what is the difference between an app that has a UIBackgroundMode key of location and an app that uses the significant-change location service in the background?
An app that uses the significant-change location service is suspended until a location change occurs, then it is woken and can do stuff in the background. However my research shows that an app with a UIBackgroundMode of location can also be suspended, therefore what is the difference?
The significant-location-change is special , it gets delivered to suspended apps and also if the app is not running it is started & moved to suspended state to handle the significant-location-change event. If you are only using significant location update then the UIBackgroundMode key of location is not required, The UIBackgroundMode key of location is required only if you use standard location change updates (i.e using startUpdatingLocation method) and need these updates to be delivered to the app when it is suspended also.
