I want to create an Android application to use my tablet as door opener.
The door opener system is connected to my router and with the internal telefons I´m able to open the door e.g. if I dial the internal number of the door opener system.
Within my app I want to have e.g. a Button. If the button is pressed the internal number of the door opener should be called and so I can open the door.
The second thing would be to speak over the app with the person who rang the bell. So the app should have phone capabilities but I don´t want to use the system own phone dialog. I want to do this within my app.
Which API I have to use? I have installed the app FritzAppFon on my device and with this app I can do telephone calls (external and internal). Cause of this I think it should be possible to create such a app.