Foreground refers to the active apps which consume data and are currently running on the mobile. Background refers to the data used when the app is doing some activity in the background, which is not active right now .
Read moreWhere are the background apps in Android?
Open the Settings option on the phone. Look for the section called “Application Manager” or simply “Apps”. On some other phones, go to Settings > General > Apps. Go to the “All apps” tab, scroll to the application(s) that’s running, and open it.
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