Hello, I’m working on a caller ID app and with the release of iOS 18.2, Apple has introduced the ability to set a third-party app as the default calling app. I have followed the official documentation for this feature and successfully set my app as the default phone app for making and receiving calls.
Documentation Reference: https://developer.apple.com/documentation/callkit/preparing-your-app-to-be-the-default-calling-app
Now, I’m facing some challenges and need some guidance:
Custom UI for Incoming Cellular Calls: Is it possible to show a custom UI when receiving SIM-based cellular calls (not VoIP)? I want to replace the default iOS call screen with my own design when a cellular call is received. Can CallKit allow me to manage and display this custom UI for real cellular calls?
Detecting Incoming Cellular Calls: Can I detect incoming SIM-based cellular calls when my app is set as the default calling app? I would like to track and show details of incoming calls (e.g., caller information, call duration) using a custom interface.
Displaying Call Data (Call Duration, Recent Calls): Can I show call data (e.g., call duration, recent call history, etc.) for SIM-based cellular calls within my app when it is the default calling app? I need to know if it’s possible to retrieve and display this data in a custom format.
Managing Outgoing Cellular Calls: For SIM-based outgoing calls, can I handle the process of initiating the call and then show a custom UI for the call in progress (similar to how VoIP apps manage outgoing calls)?
I understand that CallKit can be used to manage the UI for calls, but I’m unsure about the limitations when it comes to real SIM-based cellular calls. Is it possible to implement these features with the current API capabilities, or are there any restrictions I should be aware of when managing cellular network calls?
Thanks in advance for your help!