Enlist different background modes

Ans : 

There are different background modes provided from apple and we can see them under Signing & Capabilities > + Capability (New) > Background Mode

Switch on background mode and select which is required in our project.

Background Modes in iOS

1. Audio, AirPlay and Picture in Picture
2. Location updates
3. Void over IP
4. External accessory communication
5. Uses Bluetooth LE accessories
6. Acts as a Bluetooth LE accessory
7. Background fetch
8. Remote notifications
9. Background processing

For tutorial, I recommended raywanderlich.com article