Friends, let me tell you if your phone is 4G but not volte and you are thinking to buy a new phone for such a mere reason than wait for a while and read this. Jio 4g voice is actually a app for the phones which donot have voice over LTE technology. Actually it means that without this you would not be able to make call via 4G network. Since about 2 million people are using Jio sim and networks. And since jio provides you a simple technique of making call over LTE network. But many people are not able to use this facility so in order to make it world wide, Jio 4G Voice is launched. Now you can make call over LTE. Volte Phones do not require this app. But there is one thing to make sure in non volte devices that those who are using Jio 4G voice should have jio sim ofcourse and their data connection on jio sim should be on all the time because without the LTE jio connection the app goes online making it impossible for the user to make call.