To use, internet access through Wi-Fi or 3G line is required. If you deal with a vast amount of data via 3G line, it is mandatory to use a flat-rate system of packet communication. Therefore, "free" in this context means "free based on flat-rate system."
PHYTTER requires: an internet connection (at least 150kpbs), headsets, and a webcam if using the video phone feature.(Please note that the audio and video quality may vary depending on your internet connection speed.)
You cannot make emergency calls such as 911 by PHYTTER. For your safety, please make sure to have a communication device other than PHYTTER for emergency calls.