How to Book Jio Phone? You can use MyJio App to Book your very First Jio Phone. So to pre book a Jio Phone, Open MyJio App & Tap on Pre Book now. Then Provide your Contact Number and the Area Pin Code. That’s it…You will get your Pre Booking ID Number on the MyJio App Screen as well as SMS. You need to Keep that Booking ID Number because it will be mandatory to show the Number at the time of Receiving the Jio Phone Device.