I'm using my cellphone connected to my home wireless router as a voip phone. Samsung Galaxy Note 4 cellphone; Android 5.0.1; Zoiper 1.23 for Android; paid version.
My ATT modem/router allows for "certain services forwarded directly from the internet to a particular device" under the Firewall Advanced settings. There are voip services listed here (such as AIM Talk, Dialpad, etc) but not Zoiper. Would it be helpful to set this up for the Zoiper app, if it's even possible? If it would help, here's what's needed to set up a custom service:
Global Port Range
Base Host Port
Protocol: both, udp or tcp
In general, are there any wireless router settings that can help with voip call quality? Any suggestions would be much appreciated.