I have been using GrooveIP to make calls and my wife called her mother in the Philippines a few times. It works well but her mother hears an echo when she talks. We had her on the speakers with the Nexus sitting on the table. Is the feedback coming from the speakers, back into the microphone? Is there a setting to eliminate this? My wife used some old Blackberry earphones with a built-in microphone and that seemed to eliminate the echo but she wasn't thrilled with being wired to the Nexus. If we can't get this working better I guess I am back to going to the store to buy phone cards.