Vivo v5 does not support VoLTE. So if you want to use a jio sim card in this phone so you need to install jio4G voice and have your data connection ON all the time for making and recieving calls on your jio number. As far as the sound quality is good enough. This phone is a little tricky to operate. The style and design of this phone is good. But it lacks the most important feature of supporting VoLTE. It consumes lot of battery power for making your data connection ON. The look of this phone is same as other phones of vivo. No improvement in looks. Phone is costly enough.