Here's the issue: I have a N7 2013 LTE which I've unlocked/rooted. I've enabled SMS and installed the Google Dialer. Everything works well; I can send/receive SIP calls via the dialer and I can even answer calls with my Bluetooth headset because the SIP calls received by the Google dialer are perceived as actual phone calls by Android.
This falls apart when I want to use a third-party SIP/VoIP app. I can answer native SIP calls with my Bluetooth headset (a double-tap on the headset for the Jawbone ERA), but can't do so with a third-party app. I'm guessing that's because calls answered by the Google dialer are seen as real phone calls whereas those answered by a third-party app are media events, so the Bluetooth headset isn't notified of an incoming call. This even happens with CSipSimple set to integrate with the native dialer.
CSipSimple is a great app, but it suffers the fate of any app when left in memory too long: it gets kicked out. I can watch the SIP registration status at my SIP provider's website while CSipSimple is running in the background. CSipSimple stays registered for a while, then the status switches to disconnected. If I disable CSipSimple, the native dialer registers with my SIP provider and stays registered.
Can anyone confirm or deny any of this? Is there a way to have a third-party SIP/VoIP app act like the Google dialer? Or am I stuck with the native dialer?