Status bar indicators

You can distinguish some of active background tasks in the status bar:

Location Services / GPS: When in use, the location icon appears in the status bar. You may also see a blue, double-height status bar if an app is has turn-by-turn navigation on. If an app is using Location Services, such as geofence or turn-by-turn navigation, you can pause the service within the app.

Note: You can view a list of apps that recently used location services in Settings > Location Services. Learn more about Maps and turn-by-turn navigation.
iTunes syncing: When the syncing icon appears in the status bar, the device is tethered or wirelessly syncing with iTunes.
Network activity: When the network-activity icon appears in the status bar, network activity is occurring in the current app. The network-activity indicator will appear only for the following features or activities, when you're using the corresponding app:
- Photo Stream uploads and downloads
- Regular application downloads and updates from App Store and Newsstand
- Automatic downloads (music, books, and applications)
- iTunes Match downloads
- Checking email
- iCloud restores

Third-party apps also use the icon to indicate network activity.