PushKit + CallKit for opt-in monitoring alerts?

An API event would trigger an incoming call, displaying the monitoring channel as the caller. Answering would acknowledge the alert and end the call, without establishing a voice connection.

Just to clarify, what is CallKit providing here that couldn't be solved using standard push?

Are either of these approaches permitted, or is a network-based voice connection required?

I think this very much depends on the details of exactly what you're product is "for" and how it works. The general requirement here is that CallKit/voip is "apps that people use to call people", not as a general purpose tools that replaces standard APNS.

Having said that, CallKit also doesn't have any particular restriction/requirement about how apps are actually implemented. I don't know whether what you've described here would be acceptable:

Alternatively, the app could read the alert locally using AVSpeechSynthesizer after answering.

Are either of these approaches permitted, or is a network-based voice connection required?

...but I don't see ANY issue with an app did a more "complete" solution like this:

• Used voice to text to transcribe a message.

• Sent that message as text within the voip push payload.

• Used text to speech to play the message once the call was answered.

• Allowed the user to transcribe their own message in reply.

• Sent that message "back" as a voip push to the original caller.

I'll also note that the larger app context is very important. For example, I don't see any issue with an app that included exactly the feature you're describing but also implemented standard "person to person" calling. The problem with what you're describing isn't that it it's misusing CallKit (I don't think it is) it's that, on it's own, it might not be sufficient to justification.

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Kevin Elliott
DTS Engineer, CoreOS/Hardware