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Question

What should be the correct approach to identify time spend around a beacon[not within a region] in background. I am able to do this when app is in foreground using didRangeBeacons and some business logic.I read on few forums that ranging does work when app has registered for location updates in background, but i am having no success. I have added the location updates key for UIBackgroundModes in plist.

I am using estimote beacons and their sdk.

Answer 1

I see two possible solutions here:

1. Listen for enter and exit region events, store the timestamps and then use them to calculate the time span on exit. If you define your region so that it encompasses only one beacon, monitoring the region will be equivalent to monitoring the beacon. The only thing to keep in mind is that iOS imposes a limit of 20 regions to be monitored at the same time - so this solution doesn't scale above 20 beacons.

2. Use ranging in the background. Apart from the UIBackgroundModes , you also need to start regular location services, ie startUpdatingLocation .

   Beacon ranging delivers events normally while an app is running in the foreground. When your app is in the background, this service delivers events only when the location-updates background mode is enabled for the app and the standard location service is running.

   (this is from CLLocationManager class reference , section "Using Location Services in the Background")

   Note that ranging in the background will be draining the battery life more than usual, and Apple also requires justification for using the background modes. Unless there's some value for the user of your app coming from the background modes, they might choose to reject it. All in all, use the background ranging wisely! (: