I'm using this app to receive calls from friends but it doesn't always notify (ring) when someone is calling me and when this happens I can hear the notification sound for a missed call a few minutes later. Also, ppl always have to call me twice in a row because they can't hear me during the first call. I've contacted them and they always give me the same message aka to uninstall and install the app again. I've got a great wifi and phone so the problem is on their side.