Call Initialization

For call UI you need to do following setup, so the call feature can work properly

In your project target, select signing & capabilities and add Background capabilities.

Goto Project -> Target -> Signing & Capabilities -> Click + at the top left corner -> Search for the capabilities below and add it

Capabilities
App Groups
Background Modes

Now, go to the background mode and enable the below given modes

Background Modes
Audio,Airplay, and Picture in Picture
Voice over IP
Background fetch
Remote notifications

Capabilities

Add Microphone privacy description in your project plist

microphone

Add Camera privacy description in your project plist

cameraUsage

Add Caller ringtone & reconnecting tone mp3 file in your project.

ringtoneFile

The file name must follow in the following manner

.mp3 file	File Name
Caller ringtone	`fly_call_ringtone`
reconnecting tone	`fly_reconnecting_tone`