All the Google Chrome windows running this app are touted to a IPTV, so you can answer a call from the browser. If you have the web page opened on different windows (it may be across some other devices like a smartphone or a smart-tv) and you get a call, the rest of the instances stop ringing when the call is answered in any of the other devices.
With Google Chrome you also will receive a notification, even though the browser is minimized.
Remember to point the tropo app voice url to the route /call and set the environment variable PHONO_APIKEY.
curl -X DELETE "http://example.com/register"