Re: how to build an fax app in android
One of ways may be contacting some fax web services via Internet (using their http protocol api ex. rest api). Of course they are usually paid, but there might be free trials. Maybe there is a way to fax something directly from phone I don't know. You may look at those topics stackoverflow.com/questions/23886829/how-to-send-fax-from-android-app quora.com/What-is-the-best-way-to-send-a-fax-from-an-Android-phone-using-just-the-phone-and-not-some-fax-server-or-service