I have an App that is part of a VoIP PBX system but which is NOT a VoIP App. It acts like a remote control that allow you to forward calls to our VoIP PBX to your cellular phone, or even setup calls to internal extensions all by using the Cellular network.
One of the features we want to implement is to indicate to other users on our VoIP PBX system that someone using our App is in an active call using the cellular network. We managed to make that work, but only whilst the App is in the foreground.
We are now struggling to find proper ways to activate a little bit of code in our App that will relay the Phone App state (RINGING, OFFHOOK, INCALL, etc...) to our VoIP PBX system. We are not a VoIP application and as such cannot utilise CallKit, and from what I understand, we cannot use PushKit anymore without using CallKit because people were abusing it to keep running their App in the background and thus reducing battery life. (Which I fully comprehend). But our app does not need to be active in the background and isn't a VoIP App, we only need it to wake up when the Phone App state changes and then do it's small networking task.
So, can this actually be done properly?
PS: To ensure the privacy of the user, the user needs to enable this feature him/herself. It is not enabled by default and can be switched off by the user as well.
