Reasons
2.16: Multitasking Apps may only use background services for their intended purposes: VoIP, audio playback, location, task completion, local notifications, etc. 17.5: Apps that include account registration or access a user’s existing account must include a privacy policy or they will be rejected ----- 2.16 -----
We found that your app uses a background mode but does not include functionality that requires that mode to run persistently. This behavior is not in compliance with the App Store Review Guidelines.
We noticed your app declares support for location in the UIBackgroundModes key in your Info.plist but does not include features that require persistent location. specifically, it would be appropriate to revise your app to use significant-change location services to achieve the functionality you have described.
Since your application does not require persistent, real-time location updates, we recommend using the significant-change location service or the region monitoring location service.
For more information on these options, please see the "Starting the Significant-Change Location Service" and "Monitoring Shape-Based Regions" sections in the Location Awareness Programming Guide.
If you choose to add features that use the Location Background Mode, please include the following battery use disclaimer in your Application Description:
"Continued use of GPS running in the background can dramatically decrease battery life."
----- 17.5 -----
We also noticed that your app includes account registration or access to users’ existing accounts but does not include a privacy policy, which does not comply with the App Store Review Guidelines.
Please update your app metadata to include a privacy policy and ensure that the privacy policy URL you provide directs the user to the intended destination.
If your iTunes Connect Application State is Rejected, a new binary will be required. Make the desired metadata changes when you upload the new binary.
NOTE: Please be sure to make any metadata changes to all App Localizations by selecting each specific localization and making appropriate changes.
For discrete code-level questions, you may wish to consult with Apple Developer Technical Support. When the DTS engineer follows up with you, please be ready to provide: