I am trying to make an app for making calls from app to app and app to phone. I want to know what is ,
-the process to connect the call from my app to the server and server to the client app (app-server-app)while both are having active internet connections
-the process to connect the app to the server and the server places the call to a PSTN or ISDN (app-server-phone) where one phone is having an active internet connection and the other one is not having an internet connection, but is connected to a GSM or other telephone network.
Being an android developer, I am not well versed with web side programming. I have only made API calls in my previous apps. Please enlighten me on what is required to make calls from WEB SERVER TO TELEPHONE, and make VOIP CALLS.
I have already researched some sdks for the same, namely -TWILIO -ASTERISK -ZOIPER -LINPHONE
and gone through App to app Call with Sinch
but this is only for making calls from app to app, I need to put a server inbetween and make the calls via server and record the duration and other data,and also make voice calls from server to telephone.
Any type or criticisms and suggestions are welcome.
you should have a PBX(Server), the app connect to PBX and make call, the PBX will route calls to another app or PSTN base on the dial plan(inbound and outbound rule), you also need to configure a VoIP provier or SIP Trunk in your PBX in order to make calls to PSTN or receive calls from PSTN.