I would like to convert my android phone into a personal pcbx (being able to perform basic automated answering based on speech and who is calling and performs hang up). Something requiring the power of Asterisk (unless you know an alternative designed for android of course).
There are a lot of tutorials on how to this through sip on rooted devices, but in my case, I want to do it using the phone number of my sim card which of course is tied to a provider that doesn’t give such option (they gave sip credentials during years but this is something now terminated) in order to reach the public switched network without any additional fees.
This wouldn’t be a problem on Linux as virtually every Linux compatible phone modules have a bridge for Asterisk.
But for Android devices, I read (I fail to remember where) that not only the modules designed for android phones aren’t provided with an Asterisk bridge, but that almost all the drivers controlling them are so closed source that it’s impossible to compile a custom kernel using them (that building is still possible but without support for the modem) and that while everything related to telephony is controlled by a daemon (I don’t remember it’s name), it has to be patched by oem because the kernel interface exposed to userland is closed source too and undocumented.
So that no apps allow controlling the hardware phone besides calling numbers and that even being root doesn’t change it.
If not, how can I perform such advanced usage?