I setup the app. Works like a charm. I did notice an interesting question during the setup which is that it asked for my cell phone number to be used in case of "poor data" network performance. I am assuming that a call must first be initiated using the app and with the voice payload via VOIP but then if some threshold is crossed it (meaning the Sonic back end) will initiate a legacy PSTN call to my cell and then connect the active call to the newly established PSTN call and drop the VOIP call..
Does anyone have details around how this works.
One specific question I have is this: can one force the app to not use VOIP but always use the PSTN option just like Google Voice app works (meaning payload is never pushed via VOIP but always via legacy PSTN call)?